Overview A drop wire clamp is not just a small component-it holds the last mile together. In aerial fibre networks the cables are subject to wind, ice and ultraviolet rays. Here is where a good clamp comes in: without it, sagging and twisting or fibre breaks are inevitable. These fittings hold up the fibre optic drop cables to poles, walls, facades or messenger wires under extreme environmental pressures as well as tensile loads. Aerial drop wire clamps: Form and function The design is simple: a clamp body, a wedge or jaw, a bail or hook. The cable lies in a groove and the wedge exerts pressure without crushing the fibre. The materials vary: stainless steel, galvanised steel, or UV stable polymer, all resisting corrosion and heat. The forces act on the surfaces of the grooves, to eliminate micro-bending. Technical note: a well made drop wire clamp will allow a mechanical pull of approximately 60 kg , which is more than enough for the usual aerial FTTH spans. The important thing is the spacing: if it is set close to a connector it can cause micro-bending; if it is too slack, it allows for sagging.