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.