Sinn Watch 556 A RS Black Vintage Cowhide 556.0141 Black Vintage Cowhide. Sinn watches are famed for their aviation inspired timepieces and this Sinn 556 A RS watch continues this tradition by bringing to life an aesthetic reminiscent of cockpit navigation clocks and their rapid and clear readability. The satinized stainless steel case measures to 38.5mm in diameter and houses the SW-2001 self-winding movement. This stunning Swiss made calibre equips the Sinn watch with hours, minutes and seconds function, a date display between 4 and 5 o’clock and a power reserve of 38 hours. The Sinn 556 A RS has a special feature that allows it to stand out from all other pilots watches in the 556 series, a bright red seconds hand which stands out handsomely against the matte black dial and the white luminous numbers and indexes. The dial is protected by high quality scratch resistant sapphire crystal glass, famed for its scratch resistance, and armed with a screw in crown and screw down exhibition case back. The case back not only assists in a healthy water resistant rating of 200 metres but it provides a delightful view of the automatic winding movement within. To complete the look of this Sinn 556 watch, a black vintage cowhide leather strap is added alongside a stainless steel buckle.