Review on 🎨 High-Quality MPS Disposable Paint Spray Gun Cup Liners and Lid System, 50 Pack - Mini Size 6 Ounce (180ml) Kit - Includes 50 Cup Liners, 50 Strainer Lids, 1 Durable Cup with Retainer Ring, and 20 Plugs by Troy Arnold

Love these mugs! Some reviews mention leaks, I haven't had any, but probably because I collect cups very carefully. The liners are cool, fall into a hard cup. Fill in paint, then put on (with filling opening and built-in filter). It's tricky, it takes a few clicks when it inserts into the liner. This should install completely, quite subtly, I suspect there will be leaks if this isn't done. Next you need to screw on the black retaining ring. This is also inconvenient, it is very easy to cross the thread. I look sideways and see how it happens. In addition, it can be screwed too tight when screwing and miss the thread, it must be "tight enough". There are no directions and very few online guides, so I'll continue. After filling and sealing, turn the cup upside down and press down with the pistol. It has a few bumps/bumps as it goes along. Once fully seated, rotate a notch to create a complete seal. Then connect the gun to the air and pull the trigger while turning the gun upside down and all the air will be sucked out of the jar leaving only the paint in the now folded liner. Very cool! This allows you to paint upside down without splattering the paint, the paint will continue to flow. If I need more paint, I use a new cup. If I have a lot of paint left, I put the cup on top of the paint can and let the unused paint drip back into the can. Overall much better than the standard metal reusable paint cup, I will never go back!