Here's a stretcher I put together that I use at home and abroad. I try to wear it for at least 5-6 hours a day and I can wear it under loose pants. Basically it's a large O-ring with a nut as an adjuster/locking feature and it's attached to a strap on my leg that has a clip style disconnect. I haven't any any issues with the bllod being cut off but it took some close monitoring at home to make final adjustments to get it comfortable yet still a continuos traction device. I've only been using it for a little while and I haven't taken a measurement to tell if it's made any difference in size but I'll post back with up dates. The device uses the same principle as the expensive ($300-$400) devices but only cost around $7.
PS To use the restroom, I enter a stall and unbuckle the strap (I can undo the strap without reaching down in my pants or pulling them down. All I do is grab the clip buckle through my pant leg and it unsnaps), urinate, pull down pants to knees, reattach strap and away I go. No need to take o-ring off penis, it's not that tight that it won't let you urinate.