This product is designed  for rock climbing. It adopts quality plastic material, nontoxic and tasteless, safe to use and feel comfortable with it.  Designing according to human body mechanics. Features: Made of quality plastic material, this rock climbing stone is rather firm and durable.Bright colors, nontoxic, tasteless and anti-ultraviolet. Installation in all directions does not affect the feel and grip of your hands.Designing according to human body mechanics, comfortable to handle and safe to use.Suitable for using in kindergartens, schools, amusement parks, underground classrooms, corridors, walls of outdoor buildings, etc.  Specifications: Condition: 100% Brand New Item: Rock Climbing Stone Material: Plastic Optional Color: Red, Blue, Black Size: Approx. 12.5 x 10 x 6cm / 4.9 x 3.9 x 2.4inch Weight: Approx. 1840g / 64.9oz Installation method. 1. Use an electric hammer to drill a 3-4 cm hole in the wall 2. Use the expansion nails to gently tap into the hole and be flush with the wall 3. Use a steel cone with a diameter of about 9 mm to spread the inner expansion nails 4. Use a screw to penetrate the rock and wring into the inner expansion nail. Use a hexagonal wrench to wring until the rock point does not slide Package List: 10 x Rock Climbing Stone 20 x Screw 20 x Nut 20 x Pad Note: Don't wring the rock too hard and break itChildren must be supervised when climbing, and safety belts must be installed if installation are too high (buffer sponge pad on the bottom)