Lightweight first gear drive flange includes factory-pressed (non-replaceable) top-notch German one-way bearing, hand-ground for optimum running accuracy and energy. The one-way bearing must be frequently serviced, washed, and oiled (we suggest utilizing # 106231 HUDY One-way Lube). Made to be properly used with new little 2 speed. CNC-machined from tough Swiss 7075 T6 aluminum