Wheels Mfg axles are made from aircraft quality 4130 alloy steel, made specifically for Wheels Mfg. Its heat-treated to increase strength without making the axle brittle. Rolled threads make for easy assembly of cones & locknuts. – Fits many BMX hubs – Type: Solid Axle – Threads: 9.5mm x 26tpi – Diameter: 9.5mm – Length: 187mm – 1 axle per bag