The invention relates to a register, which is characterized in that a mechanical register is arranged in a box so as to be used for displaying the electric quantity. The register further comprises a resistance-capacitance voltage reducing circuit, a DC conversion circuit, a far infrared communication circuit, an electric energy metering circuit and an electric quantity storage circuit. The female portion is provided with a connector, wherein the connector of the female portion is provided with an embedding port and a limiting port which are kept to be parallel to a center line of a support platform. The female portion is further provided with a first installing port which keeps an included angle of 90 degrees with the center line of the support platform, wherein the first installing port is in the shape of through slot. The opening part of the embedding port of the female portion is communicated with a circular truncated cone shaped embedding area. The head of an embedding rod of a male portion is provided with a circular truncated cone shaped block body which is in transition fit with the circular truncated cone shaped embedding area. The register provided by the invention avoids defects in the prior art that disassembly of the box is generally caused to be difficult because of strain and even that the connection is caused to be damaged.