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