Rolex Explorer II 16570, 3186 movement.

Rolex Oyster Perpetual Explorer II 16570 with the later 3186 transitional “wiggle test” movement. 40mm diameter steel case, which is water resistant to 100 meters. Self-winding, automatic calibre 3186 movement; a power reserve of 50 hours. White dial with applied luminous hour markers and luminous hands. Third red hand for second time zone. A cyclops lens date window at the 3 o’clock position. Featuring a steel, 24-hour graduated bezel. Steel oyster lock bracelet. Box and papers dated October 2011.

The Rolex Explorer II reference 16570 with Rolex is a standout model for adventurers. It featured a 40mm stainless steel case, available with black or white “Polar” dials, and a fixed 24-hour bezel. Initially powered by the Caliber 3185 movement, which allowed independent adjustment of the GMT hand, the watch was updated around 2006 with the Caliber 3186.

The 3186 movement introduced Rolex’s Parachrom hairspring, offering greater resistance to shocks and temperature variations, along with a smoother GMT hand function. Collectors use the “wiggle test” to differentiate between the two movements—if the GMT hand wiggles slightly when adjusting the time, it’s likely the 3185; the 3186 eliminated this issue.

The 16570 remained in production until 2011, replaced by the larger 42mm 216570. Today, the 16570, particularly with the 3186 movement, is a sought-after piece in the pre-owned market due to its versatility, durability, and rarity during the final years of production. Its understated design and functionality make it a favourite among explorers and collectors alike.