Accessories are removably received by a non-contact electrical detector for measuring an electrical characteristic without galvanic contact between the accessory and a non-contact sensor in the non-contact electrical detector. In some embodiments, an accessory is positioned in a gap between first and second extensions of the non-contact electrical detector. In some embodiments, an accessory includes first and second recesses on opposite sides of the accessory. First and second clamp arms of a non-contact electrical detector are inserted within the first and second recesses to removably hold the accessory. An external conductive prong of the accessory is electrically coupled, or is selectively electrically coupleable, with an internal conductive prong of the accessory. The external conductive prong is configured to be inserted into a receptacle of an electrical outlet. In use, the accessory positions the internal conductive prong within a sensing area of the non-contact electrical sensor of the non-contact electrical detector.