All copper with cutting drawing reference ,banana plug 4-24 pack Banana plugs are widely used in machines, power amplifiers, home speakers, speaker panels,etc Bannan plug with 24k gold plated precision copper provides oxidation protection. Two screws make the wire connection very , and the straight screwdriver operates The diameter of the inlet hole is 0.16 inch, which can be used to install 17awg to 6awg cable Colour: As Shown Material: metal Package Contents: 24 x Banana Connector Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.