Receptacles that have only a hot and neutral slot are called polarized receptacles. By having a smaller hot wire slot and a larger neutral slot on a polarized receptacle, the electrical current flows the appropriate way through the circuit. For safe use of these receptacles, double-insulated power tools can be used in polarized receptacle circuits. These safety features can reduce the risk of electrical shock, but once again, my advice is to replace the receptacle and rewire if needed to convert the circuit into a properly grounded circuit and receptacle.

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