It takes a standard plug. I used racers edge 4's with 20% nitro and they lasted pretty long. Aren't the OS plugs shorter than the standard plugs? I looked at some OS 8's compared to some McCoy and RB plugs and the O.S. was shorter. You would have less compression if that's the case. JamesJenkins, if you have another brand of plug handy set them side by side and let us know if they are the same length. I'm curious.