Some computers may have an electrical outlet, typically located adjacent to an outlet that is powered by a wall outlet or an uninterruptible power supply [UPS]. Another outlet on the computer can be used with a product like this to power a compatible monitor, giving you an additional wall or UPS outlet. Be careful, especially if you're doing this with a UPS, to avoid overloading the power supply. Whatever equipment you connect to the UPS, make sure it can handle what you connect to it. In any case, this product is exactly what I need and the length is what I need it for. If I need another one I will order another one.