This style of dropwire clamp had been superseded by 1970 when a new dropwire was introduced.
It consist of three parts, a thick copper body, which after more than 50 years of exposure to the elements has turned green with verdigris. A brass wedge is connected to a ring. The third part is a thin brass plate between the wedge and the drop wire itself.
At the house end, the ring was slipped over a Bracket No.22 with a spiral eye welded to a flat plate. At the pole end, a Bracket No.27 adapts a 15-Way ring head to attach the clamp. A simpler Hook, Clamp, Drop-wiring was later provided to allow the dropwire clamp to be easily attached to existing insulator spindles.
The clamp is designed for use with Dropwire No.1, which is double-D shaped black PVC with a longitudinal grove on both sides to aid splitting the two wires when terminating. The wires are solid cadmium-copper with one tin plated for identification with a diameter measured as 20lb/mile.
The drop wire clamp number 1 was superseded by a spiral clamp (Clamp Drop-wire No.3) which was cheaper and easier to use with the much thinner Dropwire No.3 which had copper plated steel conductors and grey insulation. This proved to be quite a fault liability and was replaced with thicker Dropwire No.6 also with grey PVC insulation.
