I received mine today. I got the bright orange version, figuring it would be easier to find if dropped.
I measured
internal dimensions at 3 7/8" x 3 1/16" x 1 1/4".
First impression was that it was smaller than I had visualized (even though I had the measurements from the internet
). The rounded corners are great and make it carry like a bar of soap rather than a 2x4. I am carrying it on my left rear pocket and it looks exactly like a wallet. It is the same size as a well stuffed trifold wallet.
One negative is that if overstuffed, the waterseal won't be tight enough to seal, so I had to watch that.
The large compartments are 1 1/2 x 7/8" x 1/2". I removed both small compartment modules and one large compartment module, opening up half of the box for thicker items. The remaining module comes with removable dividers that can cut each compartment in half. I put those in to make 6 compartments, which hold 5 advil or 13 psuedoephedrine or 4 foam earplugs (compressed) or 1 halls cough drop.
I am happy with it, but if you need to compress a lot of things into it, the container that Hacksaw posted above may be better as the camming action of the latch may pull the lid tighter onto the seal.