(60Pcs Car Engine Threaded Sleeve Helicoil Stainles Steel Thread Repair Insert Kit M3 M4 M5 M6 M8 M10 M12. Type: Helicoil Thread Repair Insert. 2) Because of a certain elastic, can make the load on the thread is more even, eliminate the screw and screw hole deviation between the pitch and tooth type, and can absorb vibration, thus increasing the screw thread connection strength and resistance to fatigue strength.
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