Limited edition of 856 pieces sinn watch 856 b uhr limited edition leather 856012 leather sinn watches are renowned for their nautical and aviation themed designs and this sinn 856 b uhr limited edition leather watch continues this tradition by celebrating the first deck watches developed by john harrison in the 18th century that were eventually used in the military for locating navigation and keeping to schedule the bead blasted stainless steel case which boasts especially scratch resis