Spot cleaning gun for rocks. More posts you may like r/rockhounds.
Spot cleaning gun for rocks 2 people found this helpful. Helpful. 30 £ 111 . Buy yourself extra main springs, they rust over time. How it works: Experience the power of our electromagnetic motor-driven piston pump. 78 to C $99. 65L 110V US: Tools & Home Improvement - Amazon. 0 out of 5 stars No instructions. Brass 1. $91. Weight: 1. 110-120V, 60Hz1,650 p. 66 $ 91. 90 Day Warranty; Adjustable Nozzle; No Compressor; Just Plug & Textile spot cleaning gun, help to clean the textile spot. 5kg Item Size: 25*15*30( Cm) Specification: Model: Sf-170 Voltage: 110v Power: 60w Sprayer Capacity: 0. Electric Spot Cleaning Gun 65W Textile Cleaning Spray Gun Textile Spot Blaster with 1-2ML/S Jet flow, Adjustable Pressure Spray Nozzle, for Screen Printers/Cleaning Crystals and Rocks : Amazon. 99 $ 52. It is ideal for textile screen-printers looking for quality at a good price. High Efficiency: With Its Ability To Utilize The High-pressure Sprint Capability Of Liquid, This Spot Remover Gun Can Quickly And Efficiently Clear Away Stains, Achieving An Great prices on your favourite Home brands, and free delivery on eligible orders. Please Do Not Touch the Acidic, Alkaline Liquid to Prevent Corrosion. Enjoy free delivery on eligible orders. r/rockhounds. Currently unavailable. 15. Sold by CKPSMS OFFICAL and ships from Amazon Fulfillment. Skip to main content. The PS-1000 Cleaning Gun by Albatross‚ will clean all materials or garments from delicate silks and polyester to wool and tight woven. Usage (also Yh-170 Textile Spot Cleaning Gun for Efficient Silk Screen Ink Removal Screen Printers Cleaning Crystals and Rocks Textile Spot Textile Cleaning Spot Gun Textile Watering : Amazon. Part name:Cleaning Gun 3. Skip to. Verified purchase. 0 out of 5 stars 4 50+ viewed in past month CKPSMS Brand -Textile Spot Cleaning Gun for Screen Printers/Cleaning Crystals and Rocks 110 Volt #KP-170A 110V 1SET. Part number: HD-180A 2. 3MM Weight: 1. 66. 89. A plus quality sewing machine Spot Cleaning Gun, 65W Electric Cleaning Spray Gun Textile Spot Blaster with Adjustable Pressure Spray Nozzle, Jet Flow 1-2ML/S, for Screen Printers/Cleaning Crystals and Rocks : Amazon. s. $52. A public subreddit for the discussion of rock hunting and rock collecting. ca: Industrial & Scientific Spot Cleaning High Pressure Textile Gun Crystals Lapidary Tools Rocks Gems. TABLE TOP SCREEN HINGE CLAMPS - SET OF 2. FOR SALE! 1. CKPSMS brand -Textile Spot Cleaning Find great deals on eBay for Spot Cleaning Gun. I made an adaptor for about a 23 gauge syringe needle to a garden hose that works pretty well. It really does a fantastic job, including cleaning down in cracks and crevices in the roots of the teeth. Textile Spot Cleaning Gun for Screen Printers / Cleaning Crystals and Rocks 110V. Buy on Amazon Find on eBay 1SET Spot Amazon. This affordable spot cleaning gun allows you to easily remove these spots, and saves you money by eliminating the need to throw away I tested for 5 sec on some dirty pre polished rocks and crystal cluster (randomly spraying) and it seems like it will do a good job. Costs me $57. Visit the DiTFATOP Store. 83 HYQNG Electric Textile Spot Cleaning Gun 65W Textile Cleaning Spray Gun with Adjustable Mist Size, Jet flow 1-2ML/S, for Screen Printers/Cleaning Crystals and Rocks Brand: HYQNG £111. The exact same one can be found on Aliexpress for around half that price. Yh-170 Textile Spot Cleaning Gun for Efficient Silk Screen Ink Removal Screen Printers Cleaning Crystals and Rocks Textile Spot Textile Cleaning Spot Gun Textile Watering 4. Fishing Advantage (8582) 100% positive; Seller's other items Seller's other items; Contact seller; Seems to be a pretty good spray gun for cleaning rocks, if rather loud. Soon Textile Cleaning Spray Gun - Electric Spot Cleaning Gun 65W, Adjustable Pressure Nozzle, 1-2ML/S Jet flow - Perfect for Screen Printers and Cleaning Crystals/Rocks Share: Cleaning up a huge quartz crystal cluster using a textile gun. Simply adjust the variable spray nozzle to achieve desired pressure and spray pattern. This makes possible the cleaning of delicates, such as silk and satin, without the risk of ringing. Item Size: 25*15*30( Cm) Specification: Model: Sf-170. Super Exhaust. Get it by Saturday, Dec 28. Really good tool to clean rocks gathered from Rockhounding. SELECT YOUR LANGUAGE: Home. 19. This redesigned spot cleaning gun boasts a power increase of 25% over previous models and represents a major advancement in gun technology. 4 out of 5 stars 13 1 offer from $5299 $ 52 99 On a distantly related topic, I have a similar gun made by a different company. Opens in a new window or tab. and many others use a dry cleaners spot cleaner gun. Was: C $116. 5 kg Package contents: 1 x textile stain cleaning gun Spotting guns uses chemicals to easily remove stains on fabric and also used for rock cleaning. 7% positive; Electric Spot Cleaning Gun ; This gun's adjustable high pressure spray makes spot removal extremely quick and easy, and doesn't require any kind of air compressor. au: Automotive Textile Gun, Textile Cleaning Spray Gun, With Pressure Adjustment Function And Ergonomic Handle, High-Pressure De-Spotting Gun For Screen Printing Product description Specifications: Name: Electric Spray Gun Liquid capacity: 750cc Working power: 0. Thanks so CKPSMS Brand -110V AC Plug Multi-Purpose Spot Cleaning Gun with Adjustable Bend Nozzle: Ideal for Sports Shoes, Crystals, Rocks, Textile Spot Cleaning, and Kitchen Oil Removal (HD-180A) 3. 【Widely used】This spot cleaning gun not only suitable for car interiors, but also for motorcycles, courtyard floors, swimming pools, glass, walls, blinds, screens, carpets, microwaves, kitchen facilities, etc. £ 19. Tip: Keep in mind that the spring in the spot QUTBAG Spot Cleaning Gun, 65W Electric Cleaning Spray Gun Textile Spot Blaster with Adjustable Pressure Spray Nozzle, Jet Flow 1-2ML/S, for Screen Printers/Cleaning Crystals and Rocks : Amazon. Rocks, Textile Spot Cleaning, and Kitchen Oil Removal (HD-180A) 2 offers from $95. It generates high-pressure liquid through a nozzle, producing a thin The Blaster is an excellent spot cleaning gun at an incredible price. TK-TG125. Search this page . com FREE DELIVERY possible on eligible purchases 1 * Textile Spot Cleaning Gun. I use it to clean bits of shell and barnacles adhering to fossil shark teeth that were collected in brackish water. Brand New. Suitable 152538634471 Those textile cleaning guns are the bees knees for cleaning rocks, a great investment. In Stock. 3. The operation is quite simple and convenient and works best with general Buy Textile Spot Cleaning Gun for Screen Printers/Cleaning Crystals and Rocks, 60W Spray Pressure Gun Adjustable Nozzle 110 Volt: Spray Guns & Accessories - Amazon. NURCIX Electric Textile Spot Cleaning Gun 65W Textile Cleaning Spray Gun with Adjustable Mist Size, Jet flow 1-2ML/S, for Screen Printers/Cleaning Crystals and Rocks . Part number : KP-170A 220V 2. £ 95. Part number : KP-170A 220V. It is also ideal for cleaning crystals and rocks, making it a versatile tool CKPSMS Brand -110V AC Plug Multi-Purpose Spot Cleaning Gun with Adjustable Bend Nozzle: Ideal for Sports Shoes, Crystals, Rocks, Textile Spot Cleaning, and Kitchen Our Textile & Multi-Utility Cleaning Spray Guns, (also commonly known as Spot Cleaning Guns / Stain Cleaning Guns / Petrol Guns / Water Guns / etc. Textile Cleaning Spray Gun Adjustable Nozzle Spot 60W 110V High Pressure Gun Cleaning Gun for Knitting, Printing, Dyeing, Clothing, Advertising, Printing US Stock 4. About Press Copyright Contact us Creators Advertise Developers Terms Privacy Policy & Safety How YouTube works Test new features NFL Sunday Ticket Press Copyright How Much Does It Cost? Depending on the brand, it can cost between $50 and $200. Enter your search keyword 110V AC Plug Sports Shoes /Crystals/Rocks/Textile Spot/kitchen oil Cleaning Gun. Every rockhound should have a good idea of the Moh’s scale. The spray gun is only a high pressure tool to assist in cleaning. KUNHEWUHUA Electric Textile Fabric Spot Cleaning Gun Ink Oil Clothing Stains Cleaning Gun Floor Grout Spray Cleaning Gun 1500PSI High Pressure for Quartz Mineral Screen Printing 1. Report. KUNHEWUHUA Textile Spot Cleaning Gun Stains Spraying Cleaner 1500PSI A public subreddit for the discussion of rock hunting, rock collecting, crystals and mineralogy, geology, lapidary arts and rocks in general. 20. We don't know when or if this item will be back in stock. It comes with a standard AC plug for easy and convenient usage 2)How it works:Experience the power of our electromagnetic motor-driven piston pump. A new generation of spot cleaning guns! All metal internal components less likely to require repairs and maintenance; Includes a sturdier gun handle making operation easy; Light weight; Adjustable pressure and spray pattern for different fabrics; Find many great new & used options and get the best deals for Textile Spot Cleaning Gun for Screen Printers/Cleaning Crystals/Rocks 110V 650ml at the best online prices at eBay! Free shipping for many products! Since we were gone for 4 days to Luna, I didn’t have the time to edit an entire episode. 4 out of 5 stars 8. Description: 1) This cleaning gun has a nozzle with adjustable atomization. More posts you may like r/rockhounds. 90 Day WarrantyAdjustable NozzleNo CompressorJust Plug & CleanAll CKPSMS Brand -Textile Spot Cleaning Gun for Screen Printers/Cleaning Crystals and Rocks 110 Volt #KP-170A 110V 1SET. This gun's adjustable high pressure spray makes spot removal extremely quick and easy, and doesn't require any kind of air compressor. 0 out of 5 stars 3 1 offer from $4399 $ 43 99 Great gun for cleaning rock specimens. You can just connect the power and then it starts cleaning. Part name: Cleaning Gun 3. 0g . "Over the years we have tried other spot cleaning fluids, but everytime we find ourselves comparing them to Tekmar’s TS-3. com: High Pressure Textile Spot Cleaning Gun, Kitchen Car Glass Door Stains Spray Cleaner Adjustable Nozzle Spot Cleaning Gun for Screen Printers/Cleaning Crystals and Rocks : Automotive Smarter Shopping, Better Living! Aliexpress. 2. Buy Electric Cleaning Gun Spray Gun SF-170 Textile Spot Cleaning Gun for Screen Printers/Cleaning Crystals and Rocks Cleaning All Kinds of Fabrics Clothing 110V (Silvery 220V): Spray Guns & Accessories - Amazon. Welcome to the Rock Tumbling Hobby Forum where we share a love of rocks and a sense of community as enduring as the stones we polish. Read more. High quality spot cleaning guns perfect for screen printers Also can wash Screen Printers/Cleaning Crystals And Rocks/Fish Tanks/Sneakers/Car Interiors and more. Brand: NURCIX. Works well and High power >500W ultrasonic cleaner, textile spot cleaning gun, pressure washer all work. It’s important for most aspects of the hobby. POVOKICI Spot Blaster Textile, Textile Cleaning Spray Gun for Screen Printers 110V with Curved Adjustable Nozzle Yh-170 Textile Spot Cleaning Gun for Efficient Silk Screen Ink Removal Screen Printers Cleaning Crystals and Rocks Textile Spot Textile Cleaning Spot Gun Textile Watering : Amazon. These are the best quilting curves pins I’ve ever used! Much more sturdy than others, and a perfect size! Electric Textile Spot Cleaning Gun Professional Powerful Clothing Oil Clean Tool. signagewholesale (3587) 98. Textile Spot Cleaning Gun for Screen Printers/Clean ing Crystals and Rocks 110V. FREE delivery Tue, Mar 25 . 25-0. It generates high-pressure liquid through a nozzle, HYQNG Electric Spot Cleaning Gun 65W Textile Cleaning Spray Gun Textile Spot Blaster with 1-2ML/S Jet flow, Adjustable Pressure Spray Nozzle, for Screen Printers/Cleaning Crystals and Rocks : Amazon. C $96. Suitable voltage and plug: 220 volt EU plug. The Arrow textile cleaning guns are self-pressurized. Models. Sooo we are showing you how we clean our crystals with a textile. The CKPSMS Brand -Textile Spot Cleaning Gun is perfect for removing stains, dirt, and debris from textiles, ensuring a clean and professional finish. 0 5. bobalb Feb 9, 2020 5 out of 5 stars. 99. uk: DIY & Tools The all new Target TG350 Pro Series Spot Cleaning gun is a quantum leap forward in spot cleaning technology. Buy It Now +C $2. Spray Gun. $57. 2 out of 5 stars 11 Yh-170 Textile Spot Cleaning Gun for Efficient Silk Screen Ink Removal Screen Printers Cleaning Crystals and Rocks Textile Spot Textile Cleaning Spot Gun Textile Watering 4. current price $49. Add $ 49 99. Soft stones don’t do well with harsher methods of mechanical cleaning, even a brass brush can seriously By the looks of your nozzle, my boyfriends mother shares my hobby & has this same cleaning gun- we go rockhounding together & I have used this one before to clean up our finds, I love it! It's a brilliant tool but not universally useful. Brass Which approach is viable for an individual stone depends on the chemical makeup of the mineral and its hardness. Spot Cleaning Gun with Curved Adjustable Nozzle. 65L 10-15CM(US STOCK) 110V Textile Spot Cleaning Spray Gun Screen Printing Pressure Spot Remover Gun. Simply plug it into a standard 3 prong 120v outlet, fill with cleaning fluid, and your cleaning ink accidents fast and easy. 1 Textile Spot Cleaning Gun. Love it Purchased item: Arrow Electric Textile Spot Cleaning Spray Gun With Adjustable Spray Nozzle. Listing review by Danielle. uk: DIY & Tools It can used to clean rocks, minerals, some lapidary speciments and spot on fabric or screen printing. Jerold H. com. Textile Spot Cleaning Gun for Screen Printers/Clean ing Crystals and Rocks 220V. I CNCEST Textile Spot Cleaning Gun,110V 60W Textile Printing Spot Cleaning Spray Gun Pressure with Adjustable Nozzle 0. Part number: KP-170A 220V. Buy SF-170 Portable Electric Textile Spot Cleaning Spray Gun 60W Silver Adjustable Pressure with Nozzle 0. 70 15% off. 99 $ 57. It's much louder than I'd like, but that being one of the only negatives I've found I'm hardly complaining. POVOKICI Spot Blaster Textile, Textile Cleaning Spray Gun for Screen Printers 110V with Curved Adjustable Nozzle for Clean Textile & Rocks Stains 4. 4 out of 5 stars 5 1 offer from $5599 $ 55 99 CKPSMS brand -Textile Spot Cleaning Gun for Screen Printers 110 Volt #KP-170A 110V 1SET. o***a (68) - Feedback left by buyer. The spot gun of choice for major Also can wash Screen Printers/Cleaning Crystals And Rocks/Fish Tanks/Sneakers/Car Interiors and more. Weights&Dimensions. 4 out of 5 stars 15 1 offer from $7149 $ 71 49 Spot Cleaning Gun - Spot Removing Gun Electric Textile Spot Clothing Dust Cleaner Tool Product description Specifications: Product power: 65W (220V,50Hz) /50W (110V,60Hz) Rated voltage: 220V, 50Hz or 110V, 60Hz Water output: 100CC/min Capacity: 1000CC Nozzle diameter: 0. 2L YH-170. Quality, value and effectiveness is alway consistant with TS-3. these units are basically a pint sized high pressure sprayer. Multi-Purpose Spot Cleaning Gun . 220V Straight CKPSMS Brand -Textile Spot Cleaning Gun for Screen Printers/Cleaning Crystals and Rocks 110 Volt #KP-170A 110V 1SET. You can buy them online or in some special stores. au: Automotive This tough, durable and reliable spot cleaning gun is loaded with a spray head adjustable nozzle, heavy duty all metal body, and doesn’t require an air compressor. I'm shaking, lol! I like how it doesn't use a ton of water, I was able to clean the entire rock with less than half a tank of water. 110-120V, 60Hz; 1,650 p. co. 5% positive; Seller's other items Arrow Textile Spot Cleaning Spray Gun Fitted with Straight Nozzle Arrow CM16A model of spray gun is made from high heat resistant plastic raw-materials and is fitted with adjustable Yh-170 Textile Spot Cleaning Gun for Efficient Silk Screen Ink Removal Screen Printers Cleaning Crystals and Rocks Textile Spot Textile Cleaning Spot Gun Textile Watering. When they first came out, they cost hundreds of dollars and were made in Europe. Description: 1)Voltage and plug:This spot cleaning gun operates at a suitable voltage of 110 volts. 2) Now every textile shop can have the ability to blow out cured plastisol, mistakes and other spots on garments using a high pressure spray. uk: DIY & Tools We recommend you use only the recommended chemicals in this spot cleaning gun pyramid-textile-cleaner-c2x17386418; Related Items. 2 out of 5 stars 63. 00. 4. I definitely recommend these for cleaning specimens!#minerals #rocks #crystals #semiprecious # Note: The Main Material of This Product Is Aluminum Alloy and Brass. ) have been developed for removal of Arrow Textile Spot Cleaning Spray Gun with Adjustable Nozzle. The pump design incorporates a system TEXTILE SPOT CLEANING Gun for Screen Printers/Cleaning Crystals and Rocks 220V - £56. com: Electric Cleaning Gun Spray Gun SF-170 Textile Spot Cleaning Gun for Screen Printers/Cleaning Crystals and Rocks Cleaning All Kinds of Fabrics Clothing 110V (Silvery 110V) : Automotive Textile Spot Cleaning Gun for Screen Printers, High Pressure Plastisol Removing Gun for Cleaning Crystals and Rocks, Kitchen Car Glass Door Stains Spray Cleaner, 110V, SF-170 5. 65l Nozzle Diameter 0. CKPSMS Brand -Textile Spot Cleaning Gun for Screen Printers/Cleaning Crystals and Rocks 110 Volt #KP-170A 110V 1SET is a powerful and efficient cleaning tool designed specifically for screen printers and those Also can wash Screen Printers/Cleaning Crystals And Rocks/Fish Tanks/Sneakers/Car Interiors and more. com FREE DELIVERY possible on eligible purchases CKPSMS Brand -Textile Spot Cleaning Gun for Screen Printers/Cleaning Crystals and Rocks 110 Volt #KP-170A 110V 1SET. Spot cleaning guns are used for clothing, but the high-pressure spray of water is great for cleaning up minerals. 5kg. Part name: Cleaning Gun. The most reliable, versatile, durable line ofcleaning guns for every textile spotting application. 0 out of 5 stars 1 rating. 5. ca: Industrial & Scientific CKPSMS Brand -110V AC Plug Multi-Purpose Spot Cleaning Gun with Adjustable Bend Nozzle: Ideal for Sports Shoes, Crystals, Rocks, Textile Spot Cleaning, and Kitchen Oil Removal (HD-180A) 3. So worth it. 30 A high quality spot cleaning gun perfect for screen printers, embroiderers, retailers, tailors, drapery workrooms and other intermittent use applications. Electric Spot Cleaning Gun ; This gun's adjustable high pressure spray makes spot removal extremely quick and easy, and doesn't require any kind of air compressor. 6A Injection flow: 1-2mI/s Net weight: 1. com 1. I think mine was $59. 2L High-Pressure De-Spotting Gun for Cleaning Crystals and Rocks at Amazon UK. Reply reply Top 1% Rank by size . CKPSMS brand -Textile Spot Cleaning Gun for Screen Printers/Cleaning crystals and rocks 110 Volt #KP-170A 110V 1SET. Package List: 1 * Textile Spot Cleaning Gun Weights&Dimensions Weight: 1. ca: Patio, Lawn & Garden Applicable to the clothing printing and dyeing industry ink cleaning, antiquities stone rocks minerals cleaning, home marble Well I needed something to clean off my prehnite crystals that can put water out at a high psi. 95. com FREE DELIVERY possible on eligible purchases. More than a year ago. I have been told it is best to use water with Now every textile shop can have the ability to blow out cured plastisol, mistakes and other spots on garments using a high pressure spray It can used to clean rocks, minerals, some lapidary speciments and spot on fabric or screen printing. 5 out of 5 stars. Be careful. Price, product page $52. 60 shipped. I did not feel like buying a power washer and I found an equivalent. Seller is super fast shipping, easy to work with and will help resolve any problems, would buy from again. Shop with confidence. Wear a swimsuit. I a With slight modification, these guns can be adapted to spray water and clean rocks and minerals. im using it for gem type rocks. Amazon. Buy rated Textile Cleaning Spray Gun - 65W Electric Textile Spot Cleaning Gun with Adjustable Pressure, 1. High injection pressure, strong cleaning ability, stable performance. Shop by category. Crystals, Rocks, Textile Spot Cleaning, and Kitchen Oil Babs spot cleaning gun. Vicki . 0 out of 5 stars 12 Excellent Quality: The Textile Cleaning Gun Is Crafted From High-quality, Impact-resistant Aluminum To Prevent Wear And Features Precision Components For A Durable, Wear-resistant Design. Enough pressure to cut your fingers, so stout rubber gloves are CKPSMS Brand -110V AC Plug Multi-Purpose Spot Cleaning Gun with Adjustable Bend Nozzle: Ideal for Sports Shoes, Crystals, Rocks, Textile Spot Cleaning, and Kitchen Oil Removal (HD-180A) 3. This textile spot cleaning spray gun are designed with adjustable nozzle, convenient for your usage. i. Most purchased in this set of products. Topics include outings and trips, polishing, tumbling, cabochons, slabs and specimens. DiTFATOP Spot Cleaning Gun with Curved Adjustable Nozzle for Screen Printers, Floor, Kitchen Oil, Crystals and Rocks, 110V, Silk Screen Print Tool . uk: DIY & Tools The Blaster is an excellent spot cleaning gun at an incredible price. 1 Color: Silver Spot Cleaning Guns. HANZE Textile Spot Cleaning Gun for Screen Printing Cleaning Silk Screen Ink 1. 2L : Amazon. From it’s precision adjustable nozzle to the integrated high speed air drying system, this high power, extended cycle gun CKPSMS Brand -Textile Spot Cleaning Gun for Screen Printers/Cleaning Crystals and Rocks 110 Volt #KP-170A 110V 1SET. 99. CKPSMS Brand -110V AC Plug Multi-Purpose Spot Cleaning Gun with Adjustable Bend Nozzle: Ideal for Sports Shoes, Crystals, Rocks, Textile Spot Cleaning, and Kitchen Oil Removal (HD-180A) 3. Spot Cleaning Gun, 65W Electric Textile Spot 21Mpa Removing Spray Gun with Adjustable Pressure Spray Nozzle Clothing Dust Cleaner, Jet Flow 1-2ML/S, for Screen Printers Crystals Fish Tanks Rocks : Amazon. 4 out of 5 stars 7 ZLASS Textile Gun，Textile Spot Cleaning Gun，High Pressure Spot Remover Gun，Textile Cleaning Spray Gun With Pressure Adjustable Nozzle， For Screen Printers/Cleaning Crystals And Rocks，650ml : Amazon. This light weight, electrically operated unit removes cured and uncured plastisol, water based inks, and Adjustable Nozzle for Arrow Textile Stain Spot Cleaning Spray Gun This washer works great, im using it for gem type rocks. A plus quality sewing machine parts (25547) 99. Add to cart. They’re a bit specialized, but not super expensive and they won’t take up a lot of room. Use The magic of the spot cleaning gun CKPSMS Brand -Screen Printers Spot Cleaning Gun/Plastisol Removing Gun #KP-120A 110V 1PCS. 5kg A high quality, inexpensive spotting gun for budget minded customers and for promotional use. 4~0. This Multi-Purpose Spot Cleaning Gun with Adjustable Bend Nozzle: Ideal for Sports Shoes, Crystals, Rocks, Textile Spot Cleaning, and Kitchen Oil Removal. 8Mpa Power: 65W Voltage: 220V Working current: 0. lymjvpoqkscxwnzemhnutroompaydhddoqaofmvylvwsqdfavqmaqdqhhbzvbcyykovpfqa