A power strip (also known as an extension block, power board and by many other variations) is a block of electrical sockets that attaches to the end of a flexible cable and allows multiple electrical devices to be plugged in. As such it can be considered a type of trailing socket though that term is more often used for single and double cable mounted sockets. The term is also used to refer to the complete assembly with the power strip on one end and a plug on the other. Power strips are often used when many electrical devices are in proximity, such as for audio/video and computer systems. Power strips often include a circuit breaker to safely limit the electric power flowing through them.