Stop your bottle falling over - this rubber boot simply pushes on to the the bottom of your cylinder and gives a flat base to help prevent the bottle from falling over.
This boot will designed to fit 3L Hydrotech cylinders - we don't know if it will suit any other brands.
Charging Cylinder NOT Included
Great accessory review by Dave on 11/11/2018
Protects the base of the bottle and helps the bottle be more stable.