I use the Dorman kits from summit racing, 69 bucks a set, very hot on high. Just a tech tip I recently learned, now I absolutely love the OEM seat heaters in my 05 suburban I have stashed in CO, really warm and i can turn on just the back which is all I really wanted, so I asked the first salesman if I bought a left and right combination adjustable dial switch but instead of left and right I made it "Lumbar and Rear" and split them up if this would give me the same effect, he said yes so that's what I did, after install I was kind of let down on heat level, so when I ordered the set recently for my 5500 ram I made mention of this to this salesman, he then informed me that if the bottom isnt wired to the back all I would ever get is a "low" setting regardless of switch postion, he is right, I unplugged my separate harness and put them per spec and bam these babies are hot now, kind of a bummer (literally ) as usually I just want the back on, just a tip to anyone thinking of doing this.