ProActive Gel Electrodes, RoundSelf adhesive, pre gelled & reusable Electrodes for use with most TENS and muscle electro stimulators Built in conductive gel surface remains effective for up to 30 uses Flexible cloth backing allows the electrode to easily and durably conform to all body surfaces Pre wired and pre gelled for easy and convenient application Long lasting, hypo allergenic gel keeps skin soft Round for prevention of electrode curl up Anchored pigtail prevents wire pull