扭力保护筒夹,又名索嘴，夹头。主要用在攻丝机上，起车载保护作用，保护丝锥不断，夹头里面有弹簧片和玻珠，机器利用夹头工作的时候，里面的弹簧片就会打滑。
价格便宜！经济！以轻便、灵活、高效
适用于所有机械制造行业，机床、模具机械、塑胶机械、印刷机械、包装机械制造厂、工程机械、汽车摩托车零部件
规格有俩种，一种是国标ISO,一种是日标JIS
公制丝锥规格 | 国标 | 日标 | 英制丝锥规格 | 英制丝锥圆柄D1*D2方柄 | 管螺纹（喉牙）丝锥规格 | 管螺纹丝锥圆柄D1*D2方柄 |
M2 | 2.8*2.25 | 3.0*2.5 | | | | |
M3 | 3.15*2.5 | 4.0*3.2 | 1/8 | 4.0*3.15 | | |
M4 | 4.0*3.15 | 5.0*4.0 | 5/32 | 5.0*4.0 | | |
M5 | 5.0*4.0 | 5.5*4.5 | 3/16 | 5.5*4.5 | | |
M6 | 6.3*5.0 | 6.0*4.5 | 1/4 | 6.0*4.5 | | |
M8 | 6.3*5.0 | 6.2*5.0 | 5/16 | 6.2*4.5 | | |
M10 | 8.0*6.3 | 7.0*5.5 | 3/8 | 7.0*5.5 | PT1/8 | 8.0*6.3 |
M12 | 9.0*7.1 | 8.5*6.5 | 1/2 | 9.0*7.1 | | |
M14 | 11.2*9.0 | 10.5*8.5 | 9/16 | 11.2*9.0 | PT1/4 | 11.2*9.0 |
M16 | 12.5*10.0 | 12.5*10.0 | 5/8 | 12.5*10.0 | | |
M18 | 14.0*11.2 | 14.0*11.0 | 3/4 | 14.0*11.2 | PT3/8 | 14.0*11.0 |
M20 | 14.0*11.2 | 15.0*12.0 | | | | |
M22 | 16.0*12.5 | 17.0*13.0 | 7/8 | 16.0*12.5 | | |
M24 | 18.0*14.0 | 19.0*15.0 | | | PT1/2 | 18.0*14.0 |
M27 | 20.0*16.0 | 20.0*15.0 | | | | |
M30 | 20.0*16.0 | 23.0*17.0 | 1/8PT | 8.0*6.3 | PT3/4 | 23.0*17.0 |
M33 | 22.4*18.0 | 25.0*19.0 | 1/4PT | 11.2*9.0 | | |
M36 | 25.0*20.0 | 28.0*21.0 | 3/8PT | 14.0*11.0 | | |
M39 | 28.0*22.4 | 30.0*23.0 | 1/2PT | 18.0*14.0 | | |
M42 | 28.0*22.4 | 32.0*26.0 | | | | |
M45 | 31.5*25.0 | 35.0*26.0 | | | PT13/8 | 35.0*26.0 |
M48 | 31.5*25.0 | 38.0*29.0 | | | PT11/2 | 38.0*29.0 |
M52-M56 | 35.5*28.0 | | | | | |
| | | | | PT1 | 26.0*21.0 |
| | | | | PT11/4 | 28.0*21.0 |
