The Vertical Double 32mm Coil has very small figure of eight windings with 18mm and 46mm outer diameters (32mm mean winding diameter). It has an open design in the middle to increase stimulating site view. It is not, however, a cooled coil yet remains quite suited to rodent and primate stimulation. The stimulating coil's cable comes out from the top and, together with the small vertical design of the coil, allows two to be positioned next to each other for dual site stimulation for larger head sizes.