The mountain-shaped clamp is a matching accessory for concrete formwork fastening, often used together with a through-wall tie rod and a mountain-shaped nut. It is clamped on the outer side of a steel pipe or square timber; after tightening the mountain-shaped nut, it presses and secures the formwork, resisting the lateral pressure of concrete and preventing the formwork from bulging or shifting. It is generally stamped and formed from thickened steel plate, offering good toughness and resistance to bending, and its surface can be painted for rust protection. It is widely used in formwork projects such as housing construction, basements, and water tanks. It is easy to assemble and disassemble and can be reused many times.