These precisely machined adapters convert your standard 911 front struts (with 3.5" bolt spacing) to allow you to mount Boxster calipers while running the beefy 1984-89 Carrera vented rotors. EXTREME stopping power, GREAT looks, and all the while allowing you to run 15" Fuchs or larger with stock hubs. Kit comes complete with TWO adapters and high quality fasteners necessary for a quick conversion. Anodized aluminum. Requires the calipers to be swapped left to right/right to left, and thus inverted.