Thanks John, I will look at that. I want you to know that because of your earlier comments I had a great sleep last night with 2.4 events per hr. I decided to focus on staying off my back instead of just hoping to. My wife had a good tip and I want to pass it on. I wore a reasonably snug tee shirt to bed with a tennis ball between the shirt and my spine about half way up the back. A few times during the night I felt the ball and those were likely times when I would have unknowingly turned over or onto my back. I slept 6.4 hrs. on one side. I am just hoping this continues.