Light enough for high altitude XC climbs, strong enough for the fast paced, hard hitting downhill runs to follow. D400 hubs are centered around super heavy duty oversized axles. The front is convertible between 9mm QR, 9mm TA, and 15mm QR TA. The rear between 135mm QR, 135mm x 10mm TA, 135mm x 12mm TA, and 142mm x 12mm TA. Converting between axle types is a simple matter of swapping end caps. The front requires no tools, the rear, some basic wrenchs.
The rear hub features a crisp, 24 point / 15 degree engagement system via the freehub embedded 3x2 pawl system.