This is a pair of clips that can fit almost anywhere. Made of light but sturdy plastic, the spring is strong enough to stay in place, but gentle enough to be comfortable on even the most sensitive areas, with soft rubber conductive pads on the tips. They are 9mm (0.4in) wide by 40mm (1.6 in) long. Any 2mm pin will plug into the top jack.
These are unipolar electrodes, so use above the waist at your own risk.