I have dropped my BP so much. Usually falling off my bed. Almost every time it hits on the tank or carto so when I pick it up the carto or tank is crooked. It won't unscrew without using pliers and messing up the carto with pliers marks so I just pull it over straight then unscrew it and put it on straight. I though as many times as I've done this I wonder how the threads aren't getting messed up. On the 808 there's a slot cut in the threads so when you knock it over sideways it lets it flex enough so they don't break or tear the threads up. Kind of another safty feature that wasn't intended. I've come to like 808 threads the best.