(150pcs Stainless Steel M3 M4 M5 M6 M8 Rivet Nut Helicoil Thread Repair Insert Kit. Item included: 150pcs x Threaded Inserts. M8 1.25 1.5D (5PCS). M8 1.25 3D (5PCS). Material: 304 Stainless Steel. 4) Because of a certain elasticity, thread insert can even the load distribution on each thread, eliminate pitch and tooth deviation between screw and screw hole, and absorb vibration, thus increasing the screw thread connection strength and fatigue resistance.
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