This 110V 16A Extension Lead Adaptor converts a 110V 16A plug to an IEC socket which means that – when used with a 110V appliance adaptor – it allows any PAT tester to perform an insulation resistance, polarity check, and earth bond continuity test on 110V extension leads which are commonly used on building sites. The adaptor is not suitable for load/leakage or touch current tests and should never be connected to a mains socket.