Notes: Both black and white dial versions of this watch are available. The hour marks and hands are luminescent.

Mechanism: In addition to the conventional hour, minute and seconds hands, the 3187 features a 24-hour hand to display a second time zone. This movement is fitted with a Parachrom hairspring and Paraflex shock absorbers, offering greater resistance to shocks and to extreme conditions. Like all Rolex Perpetual movements, the 3187 is a certified Swiss chronometer, a designation reserved for high-precision watches that have successfully passed the Swiss Official Chronometer Testing Institute (COSC) tests. Its architecture, in common with all Oyster watch movements, makes it singularly reliable.

Family Notes: Rolex introduced the Explorer II in 1971. This watch was not a successor of the Explorer 1016, but an additional timepiece with an additional function. The Explorer II was aimed at speleologists or cave explorers, who could lose sense of time during their work. The Type II came with the additional (24) hour hand, 24 hour scale bezel and a date. The Explorer II (like the I) is a chronometer and the cases were designed to handle 100m water resistance. You only had to open a National Geographic Magazine of the 1970’s and you’d see an Explorer II ad inside.