With interchangeable scales. A versatile instrument and demonstration meter that can be converted to an a.c., or d.c. voltmeter or ammeter with selection of various ranges for each mode.With a high quality moving coil, spring controlled movement with full scale deflection of 5 mA or 100 mV d.c. The long pointer has a spade end and is clearly visible from a distance. Fitted in case with glass front and back. The instrument can be used with different dials to give different voltage and current ranges. All dials are interchangeable and each has a plug coupler to fit the instrument. The coupler connects appropriate resistors, shunts or rectifiers to convert the instrument to the range as given on the scale of the particular dial. The scales have clear bold figures and are marked on both sides to enable the lecturer also to observe the reading from the back of the instrument. A zero adjuster allows the instrument to be used for centre zero dials.One dial of range 50-0-50 mV d.c. is supplied with the instrument. In wooden case.