I'm trying to solve a mystery here. I have a size 4X horizontal Brain Cell (Sapphire, I think) that I no longer use because I've parked my Macbook Pro 15 on my desk, and carry an 11-inch Macbook Air around (either in a Ristretto or in an Imago, with an industrial felt case I sewed for it myself).

So I was thinking of trying to find a new home for the 4X Brain Cell; I hate to have it lying around unappreciated.

But when I measured it, something didn't add up. I can comfortably fit my mid-2009 MBP 15 inside the Brain Cell; it's a snug fit in the horizontal dimension, but I don't feel that I'm straining the case by any means. In fact, I like how well it hugs the sides of the computer. But when I compare the measurements of the interior of the Brain Cell with the measurements of my Macbook Pro (which by the way are the same as of the current generation of 15 inch Pros), it shouldn't fit. My Pro is 14.35 inches wide, and I'm measuring the interior of the 4X Brain Cell at only 14 inches. Am I measuring incorrectly, or is it just that there's enough give inside to accommodate a slightly larger laptop? But does that lessen the protection the Brain Cell offers?

Thanks in advance for any insight.