This Patek Philippe Annual Calendar Chronograph is Patek's first in-house chronograph movement. The 40.5mm case is inlaid in Platinum and features a grey anthracite dial with day, date & month displayed in apertures and a chronograph with both the 60-minute and 12-hour counters combined. It is protected by a sapphire-crystal and comes on a brown alligator strap with a platinum deployant buckle.