Easy Fermenting Jobs Done - Each piece in the kit is set up to work to you with the to healthy food in a simple system. you have your food submerged under your glass weight, simply place the lid. Fill your airlock 1/2with water, cap, and insert into your lid. It fits perfectly into the 6 stopper with a tight fit and no leaks, and sturdy.( Pls consider whether your container fit for extra stopper size or not buying.) This Type Never Fails -The 3-Piece airlock is the perfect for the primary fermenter, since it comes apart for easy cleaning in the event of a blow-off.If you to keep a home brewing operation, the 3-piece airlock is the only way to go. It's a cinch to take these apart and clean thoroughly. so if one goes , you can turn to your spare airlocks with ease. Colour:Transparent white Material:plastic Package Contents: 4 * exhaust valves 11.5cm 4 * No. 6 stoppers (2.48 x 3.14 x 2.68cm) 4 * sealing rings (inner diameter 8mm, outer diameter 15mm) Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.