An element made of steel wire with a semicircular cross-section, with a handle at the bend point. It protects against slipping or movement of elements placed on shafts, axles, pins or other machine elements. It is threaded through a hole drilled in the element and its free and protruding ends are bent in opposite directions. Cotter pins are used only when the protected element is not loaded with axial force or when this force is small. In such cases, a cotter pin with a washer should always be used. Cotter pins are used to protect crown nuts from self-unscrewing. Approximate weight of 1000 pieces - approx. 1.15 kg.