This is a pinch valve for 6mm silicon tubing, made from laser-cut 3mm acrylic, stacked and held together with machine screws. It's ideal for controlling the flow of air, water, fruit juice, hard liquor, or whatever you desire. It's ideal for controlling the flow of stuff you don't want to risk contaminating with a regular valve, and as a result it's intrinsically food-safe.Power and control is provided by a lightweight '9g' hobby servo; the silicon tubing is simply a push-fit into the top of the valve arrangement.The photos and video are of an earlier prototype; the uploaded design is slightly refined, but functionally identical.You can see it in action here: http://www.youtube.com/watch?v=4raXnoKUtowBolts must be at least the length specified, but can be longer. If you find M2 screws longer than 12mm for an affordable price, let me know, though!The servo I used is a Hextronik HXT900, but pretty much any cheap 9g micro servo will work. Some may require some changes to the bottom 2 layers to fit their housings.Congratulations, you've assembled a pinch valve! Give it a try!