- Top choice for aftermarket upgrades - Grooved for water displacement and fit 55mm length holders - Dura: exact specification as Shimano pads with Kool Stop's patented plow tip, thinner than Dura 2 pads - Dura 2: thicker for longer life, 7.65mm contact for narrower rims, and cut-outs to reduce weight - Carbon 1: the original carbon compound which works great for most carbon wheels but will wear quicker on fast steep descents - Carbon 2: updated formula for carbon rims, withstands steep descents with reduced wear