Description: Made of quality materials, not easy to rust, not deformed, wear-resistant, durable and not easy to be broken. Strength and offers good corrosion resistance in bad environment like high temperature, cold weather, and high humidity areas. The split in the ribbed anchors expand on two opposing sides as you tighten the screw, increased holding power, anti-rotation structure, the deep cross groove is not easy to skid when twisted. Can prevent the anchor from turning in the hole during installation, perfect for hanging a wall shelf in fairly soft drywall. Suitable for gypsum board, fiberboard, hollow board, etc. for curtains, lamps, cross stitches, frames, frames, ornaments, decorative pieces, etc. Specification: Material: Plastic+Metal. Size Chart: Style 1: Suitable for 8-9mm. Board thickness 8-15mm. Style 2: Suitable for 8-10mm. Board thickness 8-15mm. Package Includes: 50 Pieces Plastic Anchor. 50 Pieces Screws. Note: Color might be slightly different due to the color calibration of each individual monitor. Please allow slightly measuring deviation due to manual measurement.