Small Magnum™

I got the smallest size magnum since I was worried the larger sizes might hurt going in. It is very easy to insert, and the electrode arrangement front and back instead of side by side like other plugs is superior. However the insulated portion diameter is only somewhat smaller than the head diameter, so keeping it inserted during contractions can be a problem for me. On another guy I tried it on it was not a problem at all so it depends on your anatomy. For that reason I'd recommend going with at least the medium size if you can take it.