The cas be is an icon at u boat it stands for the mix of materials and the use of rugged 316l steel maintaining the patented left hook on all u boat watches this watch is as elegant as it is robust the tan alligator strap with its aero design holes are a trademark of the brand and as much as they make the watch appear smart it does not detract from the watchs 100m water proofing and exhibition window also available in 50mm