Straight clamp for straight and offset fletching. Be aware that the right helical and left helical Bitz clamps are NOT mirror images of each other. The Bitzenburger left helical is more drastic than the right helical clamp. They never advertise the fact, but the left clamp is helical pattern of 15 degrees and the right clamp is 11 degrees.

How much offset you want to have will all depend on your arrow shaft diameter and fletching length. There' s enough adjustability on the Bitz that you can have too much offset on a shaft and the ends of the fletching will be hanging off each side. [X(]