There's 5 'domes' and a tube in that pic. The heavy glass tube (laying doen at the right) is mostly for mounting a camera in one end while the other end can go inside one of the domes. That lets me get 'inside' video while using them! I'm still working on attaching a lighting setup that will illuminate deep inside without messing up the camera view.
The 3 domes in the front row are 47, 58 and 66mm (just under 2" to over 2.5") in diameter and range from 3 to 4" tall. They came from dismantled snow globes. The two in the back row are not. The one on the left is a penis pump and is about 56mm diameter while the one on the right was the inner liner from a double walled drinking cup. It's 52 - 58 mm in diameter but flares out more near the base. The pump is almost 7.5" tall and the liner just under 7".
I'm currently enjoying the liner most often. It has a more rounded end than the pump and slips in a little easier because of that. At one point I had even larger domes and managed to get one inserted that was just over a 3" diameter! I had to back down from that limit which is another story altogether.
