Fully lined with smooth conductive rubber.  Designed to be used with a constant lube feed.  Perfect for long sensuous E-stim sessions. The Electro SPT is mono-polar and requires a second electrode to complete the circuit.  Each Electro SPT is fitted with a 4mm banana socket for easy connection.

Sizing:

Sizes 30mm, 40mm, 50mm. The size refers to the internal diameter of the SPT. 40mm is by far the standard size.  Due to the way the milker works the sizes are not that critical - as long as the penis will fit inside the acrylic tube when erect. Diameter is calculated by dividing the circumference by π (3.142).

Mono-polar E-stim:

The Electro SPT is mono-polar and therefore needs another electrode to complete the circuit.