This plastic carbonation cap has been designed to suit soda bottles, coke bottles, FermZilla lids and collection containers. These are great for cleaning your keg lines, or carbonating beer quickly in a bottle, or if you simply want to take beer to a mates. Liquid and Gas ball lock compatible. This carbonation cap is also suited to any of the FermZilla products such as the FermZilla Pressure kit. Made from high quality engineering plastic, it will last a very long time. It is chemically resistant and also designed to resist impact and physical damage. The thread specification on this product is the PCO 1881 (AKA Coke bottle thread).