This lambda control system comes with a 2-position change-over switch and loom, as well as the control box and stepper motor (and is almost identical to the AEB Leonardo system). It is suitable for single-point induction systems fitted to petrol-injected engines with metal inlet manifolds, built before 1999. The engine must have a lambda probe fitted in the exhaust, either as original equipment or as an upgrade. You will need a laptop PC to set up the system. You will need the software and a lead to connect to the PC (sold separately). .