The Shimano BB-UN300 Bottom Bracket is a simple and reliable square axle bottom bracket designed for smooth and efficient pedaling performance. This bottom bracket is a replacement for both the BB-UN26 and BB-UN55 models, offering a sealed cartridge bearing system for durability and longevity.
 
Key Features:
  • Square Axle Design: Ensures compatibility with a wide range of cranksets and provides a reliable interface for efficient power transfer.
  • Sealed Cartridge Bearing: Offers smooth rotation and protection against contaminants for extended lifespan.
  • Thread Type: English threading for easy installation and compatibility with a variety of frames.
  • Width Options: Available in 68mm or 73mm widths to suit different frame specifications.
  • Stainless Steel Bearings: Provides durability and corrosion resistance for consistent performance.
  • Color: Silver finish for a classic and versatile look.

Who is it for?
The Shimano BB-UN300 Bottom Bracket is ideal for cyclists looking for a dependable and straightforward bottom bracket solution that offers smooth pedaling performance. 
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