The self-tapping thread insert is a kind of fastener that strengthens the thread, which can form a high-strength inner thread hole when embedded in a soft material such as plastic, copper. It can also be used to repair the damaged inner thread. Features:1. Made of stainless steel, it is of  high hardness and low abrasion.2. Greatly improve strength and stability of screws connection.3. With certain elasticity and even load, it is resistant to vibration to avoid loosening.4. Long service life - it can be used repeatedly.5. Easy and quick to install with only one assembly tool.6. It can also repair the damaged thread by installing into thread hole. Specification:Material: Stainless SteelQuantity: 50pcsColor: SilverPackage Weight: Approx. 192g/6.8oz Package list:10 x M3*0.5-M5*0.5   L610 x M4*0.7-M6.5*0.75   L810 x M5*0.8-M8*1.0   L105 x M6*1.0-M10*1.5   L145 x M8*1.25-M12*1.5   L155 x M10*1.5-M14*1.5   L185 x M12*1.75-M16*1.5   L221 x Storage Case Note: Due to the difference between monitors and light effect, the pictures may not reflect  the actual color of the item.Please note that the new type and old type of this product will be sent randomly, and make sure you will not mind before ordering. Enhanced Durability: These stainless steel thread inserts are designed to strengthen and repair threads, greatly increasing the strength and stability of screw connections.Ensuring an extended lifespan of your equipment. Quick and easy installation: With the self-tapping design, these inserts can be installed easily without any special tools or equipment, have a certain elasticity, load evenly, resist vibration and avoid loosening. Versatile use: This 50-pack includes threaded inserts in various sizes to make them suitable for a variety of applications and repairs, these inserts will ensure a secure and tight fit every time. Material: Made of 302 stainless steel, these inserts have excellent corrosion resistance to withstand heavy duty use, say goodbye to weak threads and hello to reliable, reinforced connections! Convenient Storage: The set comes with a durable storage box that allows you to keep your plug-ins organized and convenient for future use, everything you need is within easy reach.