These snap rings are made of black oxide carbon steel. Sizes Includes: 5mm/ 6mm/ 7mm/ 8mm/ 9mm/ 10mm/ 11mm/ 12mm/ 13mm/ 14mm/ 15mm/ 16mm/ 17mm/ 18mm/ 19mm. Good for pros and hobbyists. It has higher tensile strength, sturdiness and provides longer service life, which can provide better safety and stability.
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