"Math Dial" Geek's Watch Shows Binary Hour Indicators on the Black Dial of the Large Polished Chrome Watch with Black Leather Strap The "Math Dial" Geek theme watch has a unisex size 42mm round polished chrome case. The watch comes with a black padded and stitched leather strap. Designed with a black dial that shows binary numbers at each hour indicator. Perfect gift for a math or physics student, math enthusiast or numerologist.