I made my own, coated the inside of the socket with Vaseline with a q-tip, made a harness with bullet connectors going to a 4-wire flat, plugged them into the proper places, then filled it in with plastic epoxy. It goes in and out easily, but snug enough that it won't come out on its own. I had everything on hand, cost me $0.00. That was on my 110 with the factory plug. My current 90 had no trailer wiring, so the Walmart converter worked for it. 10 minute job.