I use medical tape to wrap my penis. I’ve gone over 3 hours at a stretch at 12.5# with no blisters. The constriction sleeve is not effective, IMO, at preventing blisters. The trick is to limit the length of the glans. Wrap with tape so that the glans cannot expand lengthwise, and you’ll prevent blisters.
BTW, I wrap my glans first with toilet paper or non-sticky wrap, so the medical tape doesn’t stick to the glans—only to the shaft just below the glans. The tape is a pain to use, but it works like a charm in preventing blisters.
The technique uses three 6” strips of tape. One goes over the top in the 12-6 o’clock direction; one goes over the top in the 9-3 o’clock direction, and one goes completely around the “neck” of the penis just below the glans.
After a few hours of hanging, my glans often looks dimpled and discolored from the wrap, but that clears up after a few minutes.
If I get back into hanging, I may try to find a more convenient wrapping technique. Maybe you can try something new for yourself.