12 GPM Hex Drive Mechanical Fuel Pump. Designed to feed serious EFI and Carbureted engines, gasoline, ethanol or methanol. The 12 GPM Hex Drive Pump must be driven by a 3/8" female hex, allowing the pump to be driven from your camshaft or off the back of a properly prepared dry-sump oil pump. It may also be mounted off the engine, or in the back of the vehicle, driven by a Heavy Duty Cable Drive like that from Waterman Racing. It can be used in high or low pressure applications. Flows u p to 12 GPM. 5,000 HP on gas, up to 2500 HP methanol. High efficiency, Gerotor pumping mechanism. Tough, Type III hard coat anodized body. CNC Machined from 6061 T6 aircraft aluminum. Hex Drive Collar with 3-bolt Enderle bolt pattern. Standard male 3/8" hex driveshaft. Includes both 1.25' barb and AN-16 Male inlet. ORB-12 female outlet port. EFI applications require high-flow bypass regulators.