I've had alot of issues with the balls being pulled in and tried alot of stuff and finally i found a solution that worked for me.
The seal will probably not be 100% tight but since in sit in the tub with the base of the pump below the water line its not really an issue - just need to repump.
So my solution is using a wettex sponge cloth with two perpendicular lines cut in the middle forming a +. Just mind that the cloth will grow when wet so make the cuts a bit smaller than your girth.
The cloth will function both as a comfort protection for your groin area and help with your balls get sucked in. I use a
X40 without the grey comfort insertion and have no problem with max preassure with the
gators. When i use the Vacu-Vin it becomes a bit more difficult to keep the balls out.
Vileda Professional - Wettex
Just did this yesterday so only tried it for one session but it was my best session so far. Ive been using the
Bathmate for over a month and I've had alot of issues with getting good workouts. Started with the
X30, bought the extra comfort rings, tried with CR, lubes, condom and finally realized that it was probably a bit to small for my girth. Got the
X40 and only got good sessions when i inserted the whole package but it kind of hurt and also restricted expansion at the base. Also got pinched by the grey comfort insert so i started bleeding. So I was really happy and surprised that the Wettex cloth worked so well - Costs 1 $ and takes 1 minute to prepare.