Small, semi-flexible surge tank/collector fits inside the main bladder to corral gas around the fuel pickup and prevent starvation during acceleration, braking, or hard cornering at low fuel levels. Not that you'll ever be going that fast, but hey, it sounds good. ATL's 3-door molded surge tank measures 5x5x6" and holds .6 gallons. Works with all ATL cells sold on the LeMons store. Specify #6 AN for 8-, 10-, or 12-gallon cells; select #8 AN for all larger sizes. There's a 20% restocking fee from ATL on returns.