YK Care&reg; 2pcs 4 in 1 DC Head 3.5mm Electrode Wire/cable Connecting Wire with Tens Ems Machine 7 copper lines inside electrode wire to resist dragging greatly Length of electrode wire about 130cm Used for digital therapy machine/slimming massager/tens machine/other health care equipmenet Snap hole diameter: 3.5mm DC head 3.5 mm