These are different than you will find elsewhere. They don't just have a sheet of flexible rubber tucked around them, they have a solid electroconductive rubber ring that snaps on to the edge for a perfect fit that doesn't come loose at inopportune moments. Use a little gel for a great suction seal. Release the pressure easily by pulling the button on the top, partially or completely. Customize the pressure by the number of squeezes on the suction gun handle. A great way to combine multiple sensations into one product!
This variety set includes two S cups for nipple stim and one XS cup for clit stim. Total of 3 cups with conductive rubber rings. Suction gun sold separately.
S is 2.4 cm
XS is 1.6 cm
Very easy to use, no adapters needed. Just plug in any standard 2mm pin lead to the hole in the squared off portion of the rubber ring.