Thread Size: M4 x 0.7mm; Hex Width: 7mm/0.27inch; Dome head head size: 7x4mm (max.d*height); Height: 8.0 mm / 0.31 inch Material: Zinc plated brass corrosion resistant to ensure lifetime use. Widely used in machinery, plumbing, electrical, furniture and fencing projects, they are used to cover exposed bolt threads. Acorn nuts prevent wire stripping and provide a decorative finish as a termination fastener, protecting against exposed screw threads. Package Content: 20 pcs X COVER NUTS NOTE: It does not include other items, the color is based on the first picture, and other pictures do not show the effect Due to the difference between different monitors, the picture may not reflect the actual color of the item. . due to manual measurement. Please allow deviation. Thanks a lot!