Looks to match the original dimensions of the SM300 pretty close.Love the look/specs/price of this one - just not 100% sold on the size. Case is 41.5mm and the case on the right it looks like sticks out past the bezel at least a couple of mm, so it the dial/bezel is maybe 40mm or less with 20mm lugs. This would definitely be the smallest piece in my collection. Will keep this one on the radar (already ordered the other 2 Borealis pre-order offerings).