I've been reliably informed, by someone I trust, that they know someone with these through the nipple.

I know, it's a bit like chinese whispers, but I do actually believe them.

Apparently, the bottom of the T is actually a disk, and the vertical rod rises therough the nipple, so that the ribbed section and ring stick out of the centre of the nipple. The wide base holds it firmly place.

Thats about all I know

Kris