The Shimano BB-RS501 bottom bracket features an enhanced seal construction to provide long-lasting performance and service life

Designed for a perfect fit with Hollowtech II 24mm crank spindles
Anodized aluminum cups are high strength and light weight
Spindle Interface Type: Shimano Hollowtech II
Series: Tiagra
BB Shell Width: 68mm English, or 70mm Italian
BB/Frame Interface: choose; English, or Italian
Weight: 92g.
Color: Silver