This is a genuine Stan's No Tubes freehub body compatible with Stans E-sync & Neo hubs. Features: Replacement freehub bodies include pawls and springs pre-installed E-Sync hubs use a fast 8.18 deg engagement with reinforced high-torque pawls XDR drivers require a 1.8mm spacer (included) for use with a XD cassette Specifications: Hub Model: Stans E-Sync & Neo Hubs Freehub: SRAM XD-R Material: Alloy Weight: 77g