Hayes HFX-MAG Complete M/C Cartridge All parts listed as El Camino compatible will also function with E.C. Trail brakes Plastic piston/2.5mm push-rod parts are no longer available -- BR4336 may be purchased to update 2-22 MAG brakes All HFX-MAG compatible master cylinder internals are designed for the current aluminum piston/2mm push-rod platform (23 and newer)