Vacuum level of pump versus Vac hanger

I have never pumped before but I have recently begun using a Vac-Hanger. I have found the vacuum applied to glans quite intense even at low weights of hanging such as 5lbs.

I’m curious if any of you have used a Vac-Hanger and would be able to tell me what kind of pumping vacuum levels a Vac-Hanger at about 5lbs would be comparable to. I have had a very great edema and even a blister when I accidentally hung a little longer than intended.