Description Self-Threading, for use with tapping screws designed for plastics. May also be available in alternate materials. Dimensions in mm. Metric Hex Spacers M4 Description Length OD Self-Tapping ID Self-Tapping Screw Quote Hex Spacer, M4 x 6MM 6 6 3.56 M4 Hex Spacer, M4 x 8MM 8 6 3.56 M4 Hex Spacer, M4 x 10MM 10 6 3.56 M4 Hex Spacer, M4 x 12MM 12 6 3.56 M4 Hex Spacer, M4 x 15MM 15 6 3.56 M4 Hex Spacer, M4 x 18MM 18 6 3.56 M4 Hex Spacer, M4 x 20MM 20 6 3.56 M4 Hex Spacer, M4 x 25MM 25 6 3.56 M4