Fahnestock clip

A Fahnestock clip is an early type of spring clamp electrical terminal for connections to bare wires.

Releasing pressure allows the tab to spring back, closing the hole and gripping the wire to form an electrically sound mechanical connection.

[4] Fahnestock clips were commonly made of phosphor bronze or spring steel and plated with tin or copper for good electrical conductivity and corrosion-resistance.

Fahnestock clips were seen on early radio receiver breadboard construction, model train power connections, and the like.

However, they remain in use in elementary schools especially, where their ease of use and visible connections make them a popular way for science instructors to teach the creation of simple circuits, and most university physics departments still have them on apparatus.