This RS PRO ST20 mains socket tester or socket master is a reliable device you can use to test a range of wiring conditions in your electrical application. The tester allows you to measure correct live, live neutral reverse, live earth reverse as well as missing earth.
It has a strong, compact and ergonomic design with a soft finger grip to guarantee it's safe and easy to use and will last for a long time. It features vivid light-emitting diode (LED) display indicators so you can clearly see the wiring status when testing sockets in your circuit.
This socket tester is compliant with US and European electrostatic control directives (ANSI/ESD S20.20:2014 and BS EN 61340-5-1:2007). This means you can be sure the risk of electrostatic discharge is reduced to a minimum.

• Current rating of 30 mA
• LED (Light Emitting Diode) display type
• Earth loop impedance test
• Three pins
• Mains power source
• Voltage of 230 V AC
• Wiring checker