Description of expansion pipe size: Punch diameter * (Model * expansion tube length) Number For example, 6mm(5x30)50pcs 6mm indicates that the drilling diameter is 6mm. (5x30):5 indicates the type of the expansion tube. 30 indicates that the length of the expansion tube is 30mm. Specification: Type: Expansion anchor Material: Iron DIY Supplies: Metalworking Features: Four serrated barbed, strong and firm, can replace plastic expansion tube Uses: red brick wall light brick foam brick concrete, etc Package Content: Expansion anchor *1 Note: 1. The product is taken in kind, but because of lighting problems, pictures may have a slight chromatism. 2. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Please consider this before the purchase. 3. Please allow slight deviation for the measurement data.