Without the pump attached to cylinder fill the cylinder with water and keep it under water. Then with the pump unattached put it under water and squeeze the pump several times to fill and "seal" the pump and vacuum line with water. Now while your erect penis is under water slip the full of water cylinder (pump not attached yet) over your penis and push it down onto your fat pad to create a suction holding the cylinder in place and still full of water. Now while still under water attach the water filled pump to the cylinder and squeeze the pump completely under water until max vacuum pressure has been obtained. You will notice the pump ball now stays squeezed shut, and won't allow any more air or water into it.
Caution: this will give as much if not more pressure to your Extreme pum as the wine vac mod does to the other non Extreme or [words=https://officialhydromaxpump.com/?uid=6&oid=2&affid=98]Penomet[/words] pumps. It can cause discoloration or bruising if done for longer periods of time. With this high pressure I recommend 3 min sets max to avoid discoloration with jelquing between sets.
Enjoy!!
Caution: this will give as much if not more pressure to your Extreme pum as the wine vac mod does to the other non Extreme or [words=https://officialhydromaxpump.com/?uid=6&oid=2&affid=98]Penomet[/words] pumps. It can cause discoloration or bruising if done for longer periods of time. With this high pressure I recommend 3 min sets max to avoid discoloration with jelquing between sets.
Enjoy!!