Replacing ancient soldered 8v radio dial light bulbs in an 80s Sherwood receiver. These connectors were the best solution to avoid soldering and crimp fasteners in a fragile environment. No instructions, so it took a couple of tries to get enough bare wire exposed within the connector. Was joining stranded and solid (1980s) wire of different gauge (16 and 22) for each connection. Open the lever, stick in the wire, close the lever. Done.I do not think these would last a long time under tension…