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