Electric Transmission Temperature Gauge;100 - 250 Deg. F; California Residents: WARNING Transmission fluid temperature is the single biggest contributing factor to the lifespan of your automatic transmission. Having an accurate, realtime measurement allows you to know when to downshift or when to take your foot out of it. Whether you are towing or simply trying to harness the power of a built or boosted motor, Auto Meters Trans Temp Gauge will give you the most accurate possible measurement for the exact temp of your trans fluid. A single wire 1/8 inch NPT temperature sender included to be installed in your transmission, transmission pan or with an optional transmission cooler line manifold is available for easy installation into a transmission cooler hard line.