Replace all the O-rings on your corny kegs with this kit.Includes large keg seal, two black orings for under the diptubes, and finally the visible orings you find on the gas in and beer out posts. We provide convenient color cues so you know which post is which even in low lighting. Green is for gas and Blue is for beverage.Beware of other kits that may include silicone gaskets. Our BUNA oring material has up to 99% less oxygen transmission into the keg than silicone seals.