Steel thread inserts can effectively improve screw connection, greatly improving the reliability. Used in all kinds of low strength materials, thread inserts can largely improve the wear resistance performance of screw connection, and avoid thread damage. Features: Steel thread inserts used in low strength materials such as aluminum, magnesium, can avoid thread damage and get a good connection performance, to enhance connection strength and improve connection condition. Used for parts that requires frequent removing, it can greatly improve service life and wear-resistance of screw thread. 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. It can prevent screw from getting loose,especially used for products requiring high coefficient of insurance. Easy to maintenance, install a thread insert into a damage screw hole, then the screw hole can be used as normal, in order to avoid workpiece loss. Specification: Material: Stainless steel 304 M4*0.7*1 D, 100pcs; M4*0.7 *1. 5 D , 100pcs; M4*0.7 *2 D, 100pcs; M4*0.7 *2. 5 D, 100pcs; M4*0.7 *3 D, 100pcs; Weight: 14g~40g / 0.5oz~1.4oz (approx.) Package list: 1 set * Threaded Inserts Note: Installed length= #D means # x diameter, for example, M4*0.7*1 D has installed length = 1D = 1 x 4 = 4mm.