The design of the Infinity cam is mainly intended to be able to adjust let off. In turn when you move the draw stop to adjust the let off it does minutely adjust your draw length. In most cases to adjust from 80% down to 65% is approx. 1/8" or less. The standard BT Post Feed cam is only available in 80% let off. The geometry of the cam is the same just ones let off adjustable and ones not. Hope this answers your question.