Which device can ensure that electrical receptacles are wired correctly?

A polarity tester is specifically designed to check the correct wiring of electrical receptacles. It works by verifying that the hot and neutral wires are connected correctly and that the ground is properly bonded. This tool typically has indicator lights that illuminate to show whether the receptacle is wired correctly (normal), has an open ground, reversed polarity, or other common wiring errors.

In contrast, other options like a magnetizer are used for magnetizing tools and have no application in electrical wiring. A multimeter, while versatile and capable of testing voltage, current, and resistance, requires a more in-depth understanding to determine if a socket is wired correctly, as it does not provide a simple pass/fail indication. A static bag, on the other hand, is used to protect electronic components from static electricity and is unrelated to wiring checks. Thus, the polarity tester is the most appropriate and direct choice for ensuring correct wiring of receptacles.