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1” (25mm) 24,000RPM

1-1/4”-2” (30-50mm) 18,000RPM

2-1/4”-2-1/2 (55-65mm) 16,000RPM

3”-3-1/2 (75-90mm) 12,000RPM

1????????????????????????????????????????

2?????????????????????????12.7?????????25.4mm??????????12.7mm???12.7mm???

3????????????????????????????????????????????????????????????????