Salsa Alternator 1.0 and 2.0 UDH Kit for post-mount brakes. This Alternator Plate set works with all Alternator 1.0 and Alternator 2.0 compatible Salsa frames to allow the use of SRAM Full Mount derailleurs or SRAM UDH. Fixes wheel in rearmost Alternator plate position (17mm back) Native 160mm post-mount disc brake compatibility (no IS adaptor required) Includes required upper non-drive side bolt (choose 16mm or 18mm length to match frame thickness) and lock nut. All other hardware is re-used from current plates or can be purchased in the Alternator 1.0 or Alternator 2.0 Hardware Kit. Requires a 12mm thru axle with 1.0TP and either a SRAM UDH or SRAM Full Mount derailleur (not included). Consult the Plate Kit instructions for recommended axle length based on the frame hub standard. Engineering Identifier Number: 06-004162