Extension reel

Some extension cords also incorporate safety features, such as a polarized plug and receptacle, grounded terminals, a 'power-on' indicator, a fusible link, or even a residual-current device (also known as a ground-fault circuit interrupter or GFCI).

Extension cords come in various lengths and thicknesses, and service duties. In general, the more power needed by the appliance, the thicker the cord should be (that is, larger wires inside). Cords to be used outdoors, in wet areas, around oils, or exposed to sunlight for long periods should be selected for such specific service. An extension reel is an extension lead that rolls up, usually into the socket end, which in some cases has more than one socket on it (often 2 or 4). Another type of extension reel hangs near the plug end and permits the user to draw the cord out by grasping the socket end.