Specification: M8*80 (bolt diameter 6MM, screw length 80MM) Quantity: 5PCS Made of 304 stainless steel, it is durable and suitable for outdoor use. It offers good rust resistance and can be used in humid environments or in contact with water without rusting. Hole size: Use a hammer drill bit with the same diameter as the expansion sleeve. Install it in an electric drill to bore into the wall. The hole depth should match the bolt length. The expansion tube should fully penetrate the wall. As long as the threaded portion is sufficiently exposed, the deeper sleeve provides a firmer hold. Note that expansion screws must be installed into a relatively rigid substrate. Tensile strength in concrete is significantly higher than in brick. When properly installed in concrete, M6, M8, M10, and M12 expansion bolts provide approximate tensile loads of 120 kg, 170 kg, 320 kg, and 510 kg respectively.