If you have a 2017-2018 Reynolds Attack, Assualt or Strike and you need a replacement SRAM XD Driver freehub, you are looking at the correct part. This is Reynolds part 21280 for SRAM XD and include the freehub body, internal seal, and washer required for use.

The removal and installation process is not complicated, but if you aren't experienced or have clear instructions, please have a certified bike technician replace your freehub.