Extension sockets are built in an extension box, which makes use of electricity in our homes, offices and various other places convenient. We would be constructing an electrical extension with the following equipment; screw-driver, nails and screws, wooden plank, flexible wire, etc. An extension board is an insulated, flexible electric wire fitted with a plug at one end and one or more outlets on the other, allowing one to plug in devices whose cords are not long enough to reach a wall outlet. The materials for the construction are as follows; 1mm Nigerian cable wire, wire clips, 13 amps socket, 13 amps plug , mahogany board, 3 inches screw nail, screw driver, and current tester. During the testing of this project work, different electronics components were used to test the extension box. A borehole DAB was used to test the efficiency of the extension box in order to determine the level of load that can be connected to the extension box. After the changing of all damaged components that were used for construction of the extension, the result proves reliable and efficient. Electrical iron, deep freezer, electronic gas cooker where used to test the extension box constructed. This shows that the constructed extension box is able to serve its intentions.