The eeWings and the included CNC aluminum bottom bracket preloader are the ultimate in stiffness and durability while only weighing a mere 400 grams ? in the same weight range as premium carbon cranks but 20% to 30% stiffer. In fact, Cane Creek has such confidence in the eeWings? quality and dependability that they are backing the cranks with a 30-day 100% satisfaction guarantee and a 10-year limited warranty. Provided in 170mm & 175mm arm length. Call for size availability.