AVO meter or Multimeter is equipment used to measure electrical quantities such as voltage, electric current, and resistance in an electronic component or the electrical circuit. There are two types of AVO meters based on how it works, namely, analog AVO meter and digital AVO meters.

Multimeter, also known as avometer, is a tester used to measure electrical voltage, current, resistance and so on. Multimeters are mainly of two types, analog and digital. Both are used for measuring and fault detection in electrical circuits.

The month of manufacture can be determined by the serial number which will be written on the scale plate at the extreme lower right-hand edge. It is in the form m(m)y-xxxx, where m is the month and y the year. The advertised price was 12 guineas in 1933 and 13 guineas in 1938.

AVOmeter is a British trademark for a line of multimeters and electrical measuring instruments; the brand is now owned by the Megger Group Limited. The first Avometer was made by the Automatic Coil Winder and Electrical Equipment Co. in 1923, and measured direct voltage, direct current and resistance.