We offer water temp sending units for factory and most aftermarket electrical gauges. These fit in the small 1/8" pipe threads on the top drivers side of our aluminum water pump housings, and work with cars which included factory temp gauges. There are two different versions of this sending unit. This one uses a small disc on the top, which a spade connector slips over and locks onto. The other style (listed separately) has a threaded stud which uses an eyelet on the end of the wire, and his held on by a nut. Order the type you need depending on which connector you have on the end of your wiring harness. Another often overlooked part which can be hard to find at times. Don't let these little items hold up your build. These are a premium part, still made in the good old US of A.