A Fahnestock clip
(also sometimes spelled "Fahnstock") is an early technology for a mechanical electrical terminal
. It consists of a single piece of flexible metal
with a rectangle punched out of one end and a loop punched out of the other. The clip is bent over itself so the loop can be pushed through the rectangular opening. A wire
can be inserted through the loop that is through the cut out, and the spring force of the clip pulling up makes an electrically sound mechanical connection.
Fahnestock clips were commonly made of phosphor bronze or spring steel and plated with tin for good electrical conductivity and corrosion-resistance.
Fahnestock clips were seen on early radio receiver breadboard construction, model train power connections, and the like. Today, they have largely been supplanted by binding posts. They remain in use in elementary school, where their ease of use and visible connections make them a popular way for science instructors to teach the creation of simple circuits.
The clip was patented 26 February 1907by John Schade Jr., assigned to Fahnestock Electric Co. Less than 2 weeks after the patent was issued they filed for reissue.