The kirban one is a little thicker than stock. Also, gently break the sharp edges on the front cover where the o ring seats against, as well as both sides of the o ring groove in the cooler adaptor. This will prevent the new o ring from being cut or pinched during install. I use fine emery cloth, dont remove a lot of material, just take the razor sharp burr off. I machined the groove in my adaptor deeper and flat on the bottom using a square bit and i use a square o ring from an oil filter. I had a lot of problems with tearing and leaking and this was the last resort lol.