Why This Watch Matters Originally designed for spelunkers, the Explorer II may not be as popular as the reference 1016, but we like it for that exact reason. The Full Story The Explorer II was first released in 1971 and was designed for cave divers. This model allowed cave explorers to read time and tell whether it was AM or PM using the orange hand 24-hour indicator. This example, with fixed steel bezel with 24-hour units, features the steel Oyster case that we know and love, but with a slightly different dial configuration. You may not be spelunking any time soon, but this is a fantastic tool watch for any wearer. The Fine Print Maker: RolexModel: Explorer IIReference: 1655Year: Circa 1981Case No: 7119405Material: Stainless steelDimensions: 39mm diameter; 12mm thicknessSapphire Crystal: No, plexiglassLume: Yes, tritiumCaliber: Automatic caliber 1575Bracelet/Strap: Stainless steel Rolex Oyster bracelet with folding clasp no. 78360, and end links no. 580Lug Width: 20mmBox/Papers: No What we Love and What You Should Know This watch is in overall great condition. The case is honest, yet has light superficial scratches consistent with the watch’s age. The dial is in amazing condition with gorgeous patina. The color of the tritium has turned a beautiful cream color while the orange hand has kept its vibrant color. The bracelet has some light scratches on it but that is normal with this kind of watch. If you're looking for a killer tool watch, this is it.