This stem adapter can be inserted into a conventional 1" or 1-1/8" headset. An A-head stem with Ø 25.4 or 28.6 mm can be attached to it. (188 g/ TW). Dimensions: Shaft length 65 mm. Shaft 1" (22.2 mm), with calibration sleeve for 1-1/8" (25.4 mm). Suitable: For A-Head stem with Ø 25.4 or 28.6 mm.