Those electrode pads connect to universal TENS units, EMS, pulse massagers and muscle stimulators that are equipped with 2mm pin connectors for charge delivery. Each pad is pre-gelled and placed on a flexible white cloth backing which makes it easy to apply and conform to different body part even around joints such as the knees, elbows and shoulders. *Reusable: Use highly adhesive gel, which is reusable and makes it easy to use and available anywhere. *Universal Compatibility: Compatible with most TENS/EMS models which equipped with 2mm pin connectors. It can make your unit working like a new. *Safe & Comfortable: These pads are not irritating. It is easy to peel off, which can ensure a safe and comfortable experience for your skin. *Premium Quality: Made of non-woven fabrics and self-adhesive, which has a long lifespan to use. *Perfect Gift: A good gift for electric muscle stimulation, pain relief, muscle shock therapy and other pain treatment. *Materials: Non-woven fabric, silicone *Quantity: 4PCS *Color: white *Pin plug diameter: 2mm/0.08in *Single wire length: 8.5cm/3.35in *Single Pad size: 5x5x0.22cm/2x2x0.09in (L x W x H) *Singles Pad weight: 6g/0.21oz *Product size: 11.3x11.3x0.22cm/4.45 x 4.45 x 0.09in (L x W x H) *Product weight: 24g/0.85oz *Package size: 14 x 16 x 0.3cm/5.51x 6.3x 0.11in (L x W x H) *Package weight: 26g/0.057lbs 1 x 4-Pack Self-Stick Reusable Replacement Electrode Pads 1 x User Manual