MR 17287 LLB Enduro Bicycle Ball Bearing Abec3 17x28x7mm

Manufacturer Part Number = MR 17287 LLB. Seals or Shields = LLB = This is a Nitrile material rubber with a steel insert. Rather than the standard 2RS type seal, by machining a groove into the inner race where the seal can rotate with better efficiency and less rolling resistance.

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