Convert your ISO B and Boost 6-Bolt hubs to fit Shimano HG, Micro Spline, or SRAM XD cassettes using our latest technology. Gen 4 conversion kits include a pre-assembled axle, driveshell, and adjusting clamp for a plug-and-play swap. Installation requires a 2.5mm hex key and a T10 Torx tool. Compatible with ISO B 6-Bolt hubs with serial numbers beginning in 851. For Boost 6 Bolt hubs with the serial number starting with 852, you'll need this part 148x12mm axle. Available with stainless steel or ceramic bearings. Available in Silver or Black. Contact info@chrisking.com with any compatibility questions.