The Track Rear hub was designed by Bill Shook to be both strong and lightweight to survive the tortures of track and fixed gear riding. The 17mm axle is oversized for stiffness while sprinting. Stout 17mm bearings and patented bearing sleeves for easy adjustability and improved bearing life. Strong track quality bolts are 3/8” x 24 Tpi and work with an easy to use 8 mm allen key socket head. Because track wheels are repeatedly taken on and off the bike, the threads are steel on steel for long life. End cap contact points are large diameter serrated steel to keep the wheel from slipping. Thick 3.5mm wide flanges for strength. High flanges give it a retro look and strengthen the wheel.