The OTC EVAP Access Port Tool, No. 6787, is designed to connect into the EVAP system line at the canister quick-connect fitting, allowing for EVAP system testing and diagnosis. It's recommend for use with the OTC LeakTamer Smoke Machine, No. 6522, to perform flow testing and leak testing based on service information procedures. The tool is suitable for all GM 5/16" EVAP line systems.