Holley 4150 Double Pumper Carburettors Are A Perfect Upgrade For Hot Street Cars And Race Vehicles With A 9.500 In Fuel Line Centre To Centre Length. The Double Pumper Is Designed For Use On Lightweight Vehicles With A Manual Transmission Or An Automatic Transmission With A High Stall And Low Rear-End Gears. These Carburettors Are Available In A Gold Dichromate Or Tumble Polished Shiny Finish Along With These Features - Dual Accelerator Pumps For Additional Fuel Under Initial Acceleration - Mechanical Secondaries For Great Performance - Dual Feed Fuel Inlets For Constant High-Volume Fuel Delivery And A Manual Choke For Easy Control Of Engine Warm Up.