E-Z-GO Battery Filling System with 2-1/2-Gallon Gravity Feed Tank Used with the battery filling system (bfs) and only distilled water is recommended for use with this gravity feed tank, and when replenishing the vehicle's battery cellsin general Tank has a gravity feed that allows for steady flow of water and will stop automaticallyto prevent overflow; clean, streamlined system prevents harmful corrosion build-up on batteries and prolongs battery life when refilled consistently and accurately Compatible for use on any e-z-go electric vehicle Used with the battery filling system (bfs) and only distilled water is recommended for use with this gravity feed tank, and when replenishing the vehicle's battery cellsin general Tank has a gravity feed that allows for steady flow of water and will stop automaticallyto prevent overflow; clean, streamlined system prevents harmful corrosion build-up on batteries and prolongs battery life when refilled consistently and accurately Compatible for use on any e-z-go electric vehicle