Highly conductive with solid copper wire inside to easily form and maintain any desired shape. The inner diameter is 1.75mm so any TENS pin will fit snugly.  

Comes in 4mm (thin) or 6mm (thick) diameter, each is 1 foot in length. Each is monopolar, requiring pairing with another electrode or pad. (They come in a U shape for you to form into a coil, etc. as your preference). 

Be sure to use water-based lubricant such as Spectragel to keep the sensations smooth and avoid hot spots. Never use any lube with silicone of any kind- it weakens and degrades the rubber.

Order thin, thick, a pair of each or a variety with both.