Wheel HTZ i30Extreme robust and durable, every wall of an HTZ rim is 25 30% thicker than traditional WTB alloy rims HTZ hubs feature a heat treated steel freehub body with six pawls Axle sleeve with 17 mm outer diameter (2 mm thicker than a standard MTB hub), while remaining compatible with all traditional 12 mm thru axles Double stacked Enduro sealed bearings at the inboard end of the driver body to further increase stiffness and extend bearing life Usage: eBike,