Product Description Size: M8*20mm Material: zinc-plated carbon steel Type: Allen screw Type of thread (pitch): coarse thread Package includes: 20pcs * insert nuts 1. [Wooden Threaded Inserts]: Wood Threaded Inserts are used for pre-flush connectors for wooden furniture. Standard hexagon socket head, smooth and flat, featuring flanged thread texture, stable structure and easy to install 2. [Applications]: These furniture nut screws are suitable for hardwood/solid wood furniture, for furniture combinations. 3. [Material]: Made of high quantity of zinc-plated carbon steel, the thread inserts are wear-resistant and very durable to use. 4. [Easy to Use]: Just drill the appropriate size hole and install with the internal hex tool; External thread with unique self-tapping design and good tensile strength can contribute to tapping and effectively prevent stripping 5. [NOTE]: The pre-drilled hole should be as deep as the length of the insert nut and any part of the bolt that can be screwed