The Quartet is a 36-H rear hub that is a rear hub with in-bound axle bolts that is guard compatible. 6061-T6 forged aluminum hub shell. 3/8?, 4130 chromoly axle bolts w/15mm 4130 chromoly female axle. Hub collars feature integrated 14mm frame slot adaptors. 6902RS sealed cartridge ball bearings. 9-T driver, 3-Pawl singular spring design and precision caged needle bearings, compatible with V1, V2 and V3 cassette drivers. Color: Black. Hub Drilling: 36. Defined Color: Black. Spoke Interface: J-Bend. Axle Type: Female. Hub Type: Rear Cassette. Axle Size: 14mm.