Citizen - Promaster Navihawk Chronograph Eco-Drive CA4660-61A Diver Mens Watch Stainless Steel White Dial 200M - Silver

The CA4660-61A has gained quick popularity for being a "Compact Tool Watch." Most pilot watches with slide rules are notoriously large, but Citizen managed to fit all the professional functionality into a 40mm case. It is often compared to the Seiko "Flightmaster" or "Speedtimer" but with the added benefit of Eco-Drive (solar) technology and a higher 200m water resistance.