I didn't buy from them just because I already get wholesale price at my local dealer, but they are sold in sets of three. My injector connectors were corroded and green with gunk. I soldered in the new ones and kind of gave myself a little more slack to deal with. (The stock harness doesn't give you much room) Oh, I also used dielectric grease on them to help prevent corrosion. If you have trouble I can dig around and get the part number. Jack H '92 n/a