I can do it for about 15 minutes and then I rest for about 15 then I’ll do it again for 15 minutes that way it doesn’t hurt for me. I always make sure that I have a full erection before I start and make sure it’s also well lubed and if it starts to hurt that’s when I have evacuated too much so I back off to where it’s not hurting. So it’s low vacuum usually around five or six (rarely does it go up to seven), on the dial. I have been working up to that level over a period of three years. This pumping P E takes time.