High Country made a cam that allowed that much adjustment. The limbs had a 10# range but the cam allowed it to be moved to 50, 60 and 70# peak weights on the same bow so, it could go from 40-70#'s. It also allowed for something like 6" of draw length adjustment and let-off adjustment from 65-80%. It was great for dealers since we didn't have to stock a whole bunch of modules but I doubt it used that cam to it's highest efficiency unless you just happen to set it where it was optimally engineered for.