I don't know, ask Tudor.
http://www.watchwallpapers.com/bbcl1.jpg
So simple, notice the ceramic balls at the sides.
http://www.watchwallpapers.com/bbcl2.jpg
I just love the look of the ribs when the safety lock it's closed, it got a racing look.
http://www.watchwallpapers.com/bbcl3.jpg