The CobraScan is a digital EOBD adaptor designed to use as a simple PC Scantool or as a diagnostic interface connected to your TEN Emission tester or smoke meter. The CobraScan simply plugs into the vehicle's standard 16 pin EOBD socket to provide a live reading of engine rpm, oil temperature during a emission test and simultaneously displays any standard DTC (Diagnostic Trouble Code) stored in the vehicles ECU memory