Well here goes part one of who knows how many for the #15. First off from what I can tell the measurements seem to be spot on. Now the crazy parts. I know everyone who sells these things has to provide the legal disclaimer but she does not and states as such provide any instructions for use. For the most part it is self explanatory. However her clever little locks are not. "Push in and turn" is one thing but there is nothing to tell you exactly how to line things up. Speaking of lining things up if you put the spiral part on wrong and do not get it lined up right it will pinch like a son of a bitch. Damn that hurt. I spent about two hours in the device until such time as the lock somehow disengaged and as my wife had to run out she just had me remove it for now ill I can figure it out later. Needless to say no sleeping in it tonight. I will say for the short time it was on it was a HUGE change in comfort for the better compared to the CB6000. A little heavy though. This was a little disappointing as the web site said it was very lightweight. Have not compared actual weight but it is slightly heavier I think than the 6K. Well more later when I have some actual facts to present.