Comprising two brass blocks fitted with plated brass 4 mm, socket terminals and mounted on a moulded base. An accurately tapered plug with a fluted plastic top is supplied and fits into the hole between the blocks providing a very low contact resistance.

This substantial four gaps bridge has, plated brass strips mounted on a wood base. Plated brass terminals with 4mm sockets are provided to reduce unwanted resistance to a minimum and the gaps are closed by removable plated brass strips which are held in position by the terminals. The 0.56mm constantan wire is stretched along the top of a metre scale subdivided into millimeters and figured every centimeter. The ends of the wire are securely clamped to the terminating strips to reduce end errors to a negligible level. Supplied with jockey. SIZE: 1.13m x 81mm x 50mm approx.

Slide wire pattern with 1 wire, 1 metre long, mounted on a polished wooden base with boxwood rule graduated 0-100cm x 1mm with three socket type 4mm terminals to enable the apparatus to be used either as a 1 metre or two metre instrument with knife edge type jockey.