The Z32 wheelset includes a new and improved hub design, the "44" hub A Beefier hub with bigger internals, featuring 108 points of engagement, help you generate more torque and transfer of power for out of saddle efforts Upgraded to a 44mm ratchet rings and offer compatibility with Shimano HG, SRAM XD/XDR, Shimano Micro Spline and Campy Ekar 13 speed The "44" hub has been updated to include a slipfit system to easily swap out end caps to accommodate, 15mm,12mm or QR axles, helping you "future-proof" your wheelset Features a 32mm deep matte alloy rim paired up with our Aero bladed PBO spokes for quick response and acceleration Light weight and is great for climbing and sprinting At 19mm internal, the Z32 wheels pair up great with 2528mm tires for quick response and acceleration while maintaining rolling resistance down Rear wheels with the HG 11sp road FH body require the 1.8mm spacer (included) for use with Shimano/SRAM 811sp HG mountain cassettes Rear wheels with the XDR driver require the 1.8mm spacer (included) for use with XD cassettes Spinergy designed Hadley aluminum freehub body Rim dimensions: 32mm deep 19mm internal Included: rim tape and truing tool