Single-bore Throttle Body And ManifoldDesigned for riders seeking the greatest possible performance gains from their fuel-injected engines For maximum tunability and performance gains an S&S Variable Fuel-Injection (VFI) module is recommended (sold separately), but any compatible, programmable module with enough capability and tuning range can be used Components must be purchased separately to complete a Single-Bore EFI assembly Made in the U.S.A. Appropriate air cleaner kit must be ordered separately.