Ritchey WCS Python Trail Grips. The heart of these new grips is Tom's patented Python self-tightening helical core design. With a spiral inner grip surface designed to literally constrict around the bar the instant that the grip starts to twist, the Python grips ensure no slippage in even the most gnarly conditions. Fastened into position with an integrated lock ring, the ergonomically shaped Python grips also feature tripledensity Kraton rubber that provides welcome support for your hands.