The King Pin has 2nd and 3rd axis adjustments. The yardage wheel location is different. On the King Pin it is in front of the riser, on the Optimizer it is even with the riser. The yardage wheel is easier to adjust (re-zero) and is removeable. This allows you to shoot multiple arrow setup's out of the same bow. All you have to do is change the wheel out.

"I hate rude behavior in a man. I won't tolerate it." Captain Woodrow F. Call

ShawBuilt Custom Bowstrings