M8 1.25 1.5D (5PCS). M8 1.25 3D (5PCS). M6 1 1.5D (10PCS). M6 1 3D (10PCS). 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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