Current Helix, TRS and XCX offerings are all considered Generation 2 cassettes. Gen 2 (sometimes called FW2) cassettes are best differentiated from Gen 1 by the use of a set screw which is found on the largest steel cog and fixes the steel section to the alloy section of the cassette. Gen 1 e*thirteen cassettes did not utilize this set screw.

See below or click here to download the pdf.

Install:

Removal: