Solid 6 mm thick, 7075 aluminum with the Markit M CNC'd throughout the front face. Complete with two spindle hole adapters (19 and 22 mm). Fits 24mm cranks without any spacer. Available Teeth: 25t, and 28t Teeth: 1/8" Bore: 15/16" Adapter: 19 and 22mm included Weight: 2.2 oz (25T)