With knurlingSurface: Chromed, polishedDIN 3124, ISO 2725-1Made In GermanyDrive: Square 12,5 mm (1/2 inches)Output: External double hexagonal traction profileKey width: 17 mmDimensions / Length: 38 mmDiameter d1 (at the output):24.1 mm Diameter d2 (on the drive): 22 mm Net weight (kg): 0.06 kg For manual operation * = Outside the DIN range