For serious racers looking for smart weight savings and optimized rotating weight, XRAY's new optional lightweight 1st gear drive flange made from 7075 T6 alu has been strategically lightened (compared to the standard #335530 flange) to reduce rotating weight without sacrificing strength or durability. Includes factory-pressed high-quality German 1-way bearing, hand-ground for maximum running precision and strength. The 1-way bearing is non-replaceable once worn out, so it must be regularly serviced, cleaned, and oiled regularly (we recommend using #309580 One-way Lube). Orange color.