This is the complete set up needed to add a valve to your Rubbermaid picnic cooler (aka Mash Tun). 1/2" Stainless Ball Valve, 1/2" Barb on the outlet, 3/8" Barb on the inside silicone seal and most importantly the correct length shank. Works well with the 9" or 12" False Bottoms which also have a 3/8" Barb.
Also works on Igloo coolers.
(Note: If you're doubtful it will work on your cooler send us a photo and we'll design the right solution for you)
