​Features of test probe YH1234 BNC Female breakout to stackable single banana plugs Material: BNC,body,brass,nickel plated Center contact,brass,gold plated;insulation,ABS Wire: 20AWG,stranding 41x0.12, PVC insulated,2.2mm OD Banana plug: body,brass nickel plated; spring,beryllium copper,nickel plated; insulation,ABS,one red,one black