Short answer
116719BLSO does not appear in the Rolex catalog. Rolex writes GMT-Master II color suffixes in French: BLRO for bleu/rouge and BLNR for bleu/noir. The base number 116719 is real. It is the GMT-Master II case in 18k white gold, produced from 2014 to 2019. Sellers use BLSO to label a white gold GMT-Master II with a blue dial. Bezel color varies between listings. Treat the suffix as a seller label, not a factory code.
What the reference number means
Rolex builds references in blocks. The digits 116 mark the case generation. The digits 719 mark 18k white gold in the GMT-Master II line. Steel is 116710, steel and yellow gold is 116713, yellow gold is 116718. The two-letter suffix names the bezel insert colors. BLRO means blue and red, the insert known as Pepsi. BLNR means blue and black, known as Batman. BLSO matches no Rolex insert code.
Factory specs of the 116719
- Case: 40 mm, 18k white gold, Oyster shape, 100 m water resistance
- Bezel: Cerachrom ceramic insert, numerals coated with platinum through a PVD process
- Dial: blue, applied white gold hour markers, Chromalight lume
- Movement: Caliber 3186, automatic, 28,800 vph, about 48 hours of power reserve
- Bracelet: Oyster, three-piece links, polished center links, Oysterlock clasp, Easylink extension
- Weight: about 170 to 180 g on a full bracelet in white gold
What to check on a 1:1 replica
- Weight. Gold is dense. A 40 mm GMT in 18k white gold on a full bracelet sits near 175 g. Steel cases of the same size land near 145 to 155 g. A plated or base metal case feels light in the hand.
- Bezel insert. Cerachrom is ceramic. The surface is glossy, the numerals are recessed, and the fill sits inside the cut. Paint on top of a metal ring is a tell.
- Dial print. The coronet, ROLEX, OYSTER PERPETUAL and GMT-MASTER II lines sit on the vertical center. Check lume color under UV light for gaps and patches.
- Cyclops and date. Magnification is about 2.5x. The date should sit centered under the lens with no shift to the left or right.
- GMT hand. On Caliber 3186 the 24-hour hand holds its position while crown position 2 jumps the hour hand in one-hour steps. Copies with a friction-set GMT hand move in a smooth sweep and drift.
- Rate. Caliber 3186 runs at 28,800 vph, which is 8 beats per second. Many copies run at 21,600 vph, which is 6 beats per second. A timegrapher shows the gap.
- Engravings. Reference and serial numbers sit between the lugs. Check font depth, spacing, and the metal mark on the case flank.
Legal note
Rolex holds registered trademarks on the name, the crown logo, and the dial text. In the United States, import and sale of counterfeit goods can lead to seizure by U.S. Customs and Border Protection and to charges under 18 U.S.C. 2320. Rolex does not service, authenticate, or supply parts for copies.
Common questions
Is 116719BLSO a Rolex reference?
No. Rolex catalogs the white gold 116719 case with the BLRO insert. BLSO is a market label used by sellers.
Does the bracelet differ from steel models?
Yes. Gold GMT-Master II bracelets have polished center links. Steel 116710 bracelets have brushed center links.
Can a copy pass a scale test?
No. Tungsten and lead-weighted copies can approach 175 g, but the balance point and the feel on the wrist differ from a solid gold case.