I bought it at Mike’s Carburetor Parts out of Chehalis WA. They have a good website. 49.00 plus shipping. Wire it into any 12 volt supply that is turned off and on by the key. The little black box with the wires going into it is the temp sensor. The instructions want it on the rear most exhaust manifold bolt. I didn’t want to mess with that brass washer and special nut, so I bolted it to the head directly above the exhaust manifold. Used an existing bolt hole. Kicks the choke off only when the car is warm. Works perfect every time.