Box Two M35 BB30 / PF30 Bottom Bracket

Box Two M35 BB30 / PF30 Bottom Bracket

Several upper-tier Box bottom brackets were engineered around Box’s Oversized Technology™ platform and developed specifically in conjunction with Box cranksets. Designed with a strong focus on pedaling stiffness and efficient power delivery, the M35 system maximizes drivetrain rigidity to reduce lateral deflection and improve acceleration response under heavy sprint loads.

By dramatically increasing spindle diameter and crank interface size, the Box M35 system creates additional space for larger bearing races and increased contact area. Material is strategically removed from low-stress areas and reinforced in high-load zones to optimize both strength and weight.

The Box Two M35 bottom bracket takes oversized technology to the extreme with a massive 35mm spindle interface developed in partnership with Praxis Works™. Combined with premium Enduro™ precision bearings, the M35 platform delivers exceptional stiffness, smooth bearing performance, and immediate acceleration response.

Important:
Modern oversized frame standards are required to support this bottom bracket and crank system.

Features:

• Oversized Technology™
• B52™ massive spindle diameter design
• Stable outboard bearing positioning
• Enduro™ long-life precision bearings
• Optimized power transfer and pedaling stiffness
• Reduced lateral deflection under load
• Immediate acceleration response

Specifications:

• Process:
  • CNC-machined cups
• Material:
  • Cups: Alloy
  • Sleeve: ABS Plastic
• Finish:
  • Anodized
• Spindle Compatibility:
  • Box / Praxis™ M35 only
• Shell Compatibility:
  • BB30
  • PF30
• Shell Width:
  • 68mm
• Weight:
  • Approx. 138g / 4.9 oz

Compatibility:

• Box One™ M35 cranksets only
• Praxis™ M35 spindle systems

Bearings:

• Premium Enduro™ precision bearings

Important Notes:

• Does NOT include drive-side bottom bracket seal
• Requires oversized frame compatibility
• Designed specifically for Box/Praxis M35 systems only