With Centerlock disc rotor mounting, the quick release HB-MT400 front hub offers stiffer wheel rigidity, smooth rotation, and less drag With Centerlock disc rotor mounting, the quick release HB-MT400 front hub offers stiffer wheel rigidity, smooth rotation, and less drag 100 x 15mm front E-THRU axle compatibility **SHIMANO HUBS ONLY AVAILABLE FOR WHEEL BUILDS**