extension cord vs power strip

extension cord

noun
  • An electrical cord with a plug one end, and a single socket or a multi-port socket at the other end, used for powering one or more devices at a distance, too far from the wall outlet to be reached by the normal cords of the device or devices. 

power strip

noun
  • A block of electrical sockets that attaches to the end of a flexible cable and allows multiple electrical devices to be plugged in. 

How often have the words extension cord and power strip occurred in a corpus of books? (source: Google Ngram Viewer )