The 3690-0 is a black do-it-yourself solder type miniature Banana Plug with nylon insulator cap, gold-plated brass body and gold-plated beryllium copper spring.
Supports 20 to 22AWG wires
Allows creation of custom patch cord lengths
Insulator unthreads to allow easy do-it-yourself wire soldering
Gold-plated body & spring for corrosion resistance & optimum electrical connection between plug/jack
Beryllium copper spring for superior spring shape retention to ensure long insertion life