Application Scope: This m4 helicoil kit is mainly used for parts that require frequent disassembly and steel thread sleeves made of low strength materials such as aluminum. Having A Certain Degree of Elasticity: due to its elasticity, the load can be evenly distributed on each thread, eliminating the pitch and pitch deviation between screws and screw holes, and absorbing vibration, thereby improving the strength and fatigue resistance of thread connections.