The CPS Products Smoke Wizard GLD-40 combines pressure and vacuum style Evaporative Emission (EVAP) system leak detection capabilities and general purpose leak detector functions in a compact design that can fit inside your toolbox. The smoke machine allows technicians to monitor EVAP system pressure or vacuum while comparing to fuel tank pressure sensor scan data to provide a quick and accurate diagnosis. It features an easy-to-read flow control knob position, vacuum and pressure decay gauge, and uses OEM-approved UltraTraceUV.