Enduro 61902 15x28x7 ABEC 5

This is a higher grade 6902 bearing.

- Grade 5 Chromium Steel Balls
- High precision balls are within 5/1,000,000" round. These are military level specification, used for precision equipment. R-64 hardness, of the highest grade.
- 52100 High Carbon Chromium Alloy Races
- Vacuum de-gassing process for the purest chromium alloy steel, hardened to R-62, extremely tough and very durable. Polished to a mirror finish for ABEC-5 precision and noiseless movement.
- Graphite/Nylon Ball Retainers
- Nylon with graphite retainers are virtually frictionless while providing constant lubrication.

The ABEC 5 Standard
To meet the ABEC-5 standard, bearing design must pass all tests, which include noise testing at high RPM, extremely close tolerances for I.D. and O.D., roundness of ball, trueness of the races and micro surface finishes of balls and races.

C-3 Clearance
This specification describes the internal clearance between the bearing and its race. For example, in a 10-18 I.D. bearing, our standard is 11-21 micrometers where as others use 11-25 micrometers.

Enduro LLB Type Seals
Our most popular seal type, this is a Nitrile material rubber with a steel insert. Rather than the standard 2RS type seal, we go a step further by machining a groove into the inner race where the seal can rotate with better efficiency and less rolling resistance. Rather than one thick seal lip rubbing on a blunt surface, LLB type utilizes two razor thin sealing lips riding in the groove with light contact. The outside lip keeps the water and contaminates out, while the inner seal retains the grease for smooth function and long intervals between servicing.