Quantity: 5PCS Specifications: Total length 90mm (3.5in), Expansion tube length 38mm (1.49in), Opening distance 16mm (0.6in), Drill bit diameter 10mm (0.39in). Made of stainless steel 304, durable and suitable for outdoor use with excellent rust resistance. Can be used in damp environments or submerged in water without rusting. Easy Installation: Use a hammer drill to create a hole in the wall matching the expansion tube diameter. Insert the expansion hook into the hole and tighten the hex nut with a wrench. As the bolt is tightened, the sleeve expands and the fins secure against the wall. Expansion mechanism: Tightening the threaded bolt pulls a tapered cone, causing the sleeve to expand against the walls of the drilled hole. Tensile strength in concrete: When properly installed, the tensile load capacity is 120kg for M6, 170kg for M8, 320kg for M10, and 510kg for M12. The tensile strength in concrete is up to five times greater than in brick.