Product Description For maximum theft protection: the Pitlock Security System for Shimano gear hubs with solid axle With this set, more security is simply impossible. The solid axles are provided with a unique code nut and can only be opened with the personal key (pit). Secures the rear wheel solid axle of the Shimano Alfine or Nexus hub with a 3/8" thread. Note:The protruding thread should protrude about 14 mm from the dropout. The retaining ring requires a free space (contact surface) of 15 mm in radius or 30 mm in diameter so that the Pitlock fastener can be securely installed. Features:Pitlock Set SH38converts in 5 minutesstainless steelresistant to weather and grime An important component of the Pitlock system is the code card, which allows the owner alone to reorder a lost key (Pit) directly from the manufacturer or a specialist dealer. Contents:SH38 single: 1 x Pitlock lock nut 3/8" for rear wheel1 x key (PIT)1 x Pitlock code card Double (SH38 double): 2 x Pitlock lock nut 3/8" for rear wheel1 x key (PIT)1 x Pitlock code card Manufacturer: Pitlock Wittestr. 3-5 Haus F 13509 Berlin Germany info@pitlock.com