The bench harness allow for flashing and recovery of an ECU outside of the vehicle. Included with the Bench Harness version 3 are a Gen 1/2 Adapter, Gen 3/4 adapter, universal adapter, 15v power supply, and the Bench Harness with power cycle switch. Useful for flashing vehicles that aren't equipped with proper OBD-II wiring. Vehicles with HVAC removed. Or for other in-vehicle diagnostic purposes.