The Rolex Explorer II reference 216570 in Polar white dial is one of the most quietly purposeful watches in the modern Rolex catalog — a 42mm GMT engineered originally for cave explorers, polar researchers, and anyone working in environments where day and night blur into each other. Released at Baselworld 2011 to mark the Explorer II's fortieth anniversary, the 216570 brought a significant case size increase from 40mm to 42mm and a brand-new movement, the Caliber 3187, never seen in any other Rolex model. The 42mm Oystersteel case carries a fixed 24-hour graduated steel bezel — distinct from the GMT-Master's rotating bezel — paired with a white lacquered dial carrying large Chromalight applied indices, Mercedes hands, and the signature orange 24-hour hand that lets the wearer differentiate day from night at a glance. Powered by the in-house Rolex Caliber 3187 with 31 jewels, blue Parachrom hairspring, variable inertia balance wheel, Paraflex shock absorbers, approximately 48 hours of power reserve, and Superlative Chronometer certification. Water-resistant to 100 meters and worn on the Oystersteel Oyster bracelet with Oysterlock clasp and Easylink extension. Produced until 2021 when it was succeeded by the 226570. 2019 production, pre-owned in excellent condition, full set. Affirm financing available at checkout.