Please be sure to choose the correct plug type for your device There are three choices. Two high-quality Tens electrode lead wires. These durable lead wires each use the 2.35mm safety plug to TWO 3.5mm snap connectors. Note: Make sure that your device uses the 2.35mm safety plug (see images above). If your device has the smaller 2.5mm port or the standard 3.5mm (headphone jack size) port then select the appropriate plug type above. Used for electrode pads that accept the industry standard 3.5mm snap connector. This lead wire is compatible with all TENS muscle stimulator devices that use the industry standard 2.35mm safety plug such as the TENS 7000 units.