When I first strap in, my timing intervals usually last 10-15 minutes without un-strapping/re-strapping, before I'm warmed up. This is on low tension. Within a half an hour to an hour of consecutive extending in this fashion, I can then extend 15-30 minutes without un-strapping/re-strapping. Initially, I extend on low tension at the beginning of my session, then move to high tension (approximately) an hour into my session. Once I master a bar setting, I usually complete three hours of consecutive extending on high tension following my first hour on low tension, I then close my session with a final hour on low tension, after three consecutive hours on high tension. Before I master a bar setting, I may start out with one hour of high tension after my initial hour of low tension, then remain at this duration until I can build my way up to two hours of high tension after my initial hour of low tension, then remain at this until I can build my way up to three hours of high tension after my initial hour of low tension etc. While un-strapping/re-strapping in the same manner as on low tension. That's why I begin with five hours of low tension with all new bar settings. Your tolerance time for high tension will always increase as the hours are completed consecutively. The same way it increases on low tension, as I demonstrated before. After three hours of high tension, I switch back to low tension and clock an hour in to allow my dick to heal in an extended state. This is an excellent trick. You can't lose with this method. It always yields gains. But be sure to strap in firmly behind the glans every time. Avoid retraction at all cost. I even like my glans to remain full in volume. Most strapping techniques will cause your glans to shrink like a raisin. I don't like this. In my mind, this is considered a form of tolerance for retraction. You never want your dick to retract while extending.
