Every so often, a new Rolex release comes along that immediately gets collectors talking. The GMT-Master II 126713GRNR, often called the “Bumblebee”, is one of those watches. Its mix of steel and yellow gold, paired with a glossy black dial and a grey-and-black Cerachrom bezel, gives it a look that stands out while still feeling familiar to the GMT line.
This reference also marks the return of yellow Rolesor to the collection, bringing back a style many enthusiasts had been waiting for. To understand why the 126713GRNR has become such a talked-about model, let’s take a closer look at its background, design, and how it wears on the wrist.
Watch our tour video about the Rolex GMT-Master II Stainless Steel – Yellow Gold / GRNR / Jubilee 126713GRNR-0001.
From the Pepsi to the Bumblebee – The Story Behind the Grey-and-Black Bezel Debut
The GMT-Master was first introduced in 1954 for pilots who needed a watch that could track two time zones at once. Over the years, it grew into one of the Rolex most known sports watch models, producing nicknames like Pepsi, Batman, and Root Beer.
The GMT-Master II, introduced in the 1980s, added an important upgrade: the local hour hand could be adjusted independently, making the watch especially useful for frequent travelers.
In 2019, Rolex discontinued the last yellow Rolesor GMT, the reference 116713LN, leaving the lineup without a steel-and-gold option for several years. That gap was finally filled at Watches and Wonders 2023, when the brand unveiled the 126713GRNR alongside a full yellow gold version. This new release brought Rolesor back into the collection and debuted a bezel never seen before in the GMT family – a grey-and-black Cerachrom insert that shifts tone depending on the light.
Collectors quickly gave the watch nicknames. The most popular is “Bumblebee”, which comes from its black-and-gold appearance. Others call it the “Zombie”, a name that came from its darker, muted bezel tones. Whatever it’s called, the 126713GRNR stands apart in the GMT line as a modern two-tone that reintroduces yellow Rolesor and debuts the grey-and-black ceramic bezel.
With that background in place, let’s take a closer look at how the case and bracelet bring the Bumblebee’s character to life.
A Case Built for Everyday Travel
Bumblebee carries the familiar Oyster case, sized at 40 mm in diameter, about 12 mm thick, and roughly 48 mm lug to lug. The case is built from Oystersteel for durability, matched with 18k yellow gold elements that give this two-tone model its character. The top surfaces of the lugs are brushed, while the sides are high-polished, creating a contrast that highlights the case lines. A screw-down Triplock crown in yellow gold, together with the solid screw-down caseback, ensures water resistance to 100 meters.
Around the case sits a yellow gold bezel with a notched edge for easy grip. The insert is made of Cerachrom ceramic in a unique grey-and-black combination, the first of its kind in the GMT line. The 24-hour numerals and markers are filled with yellow gold, with small dots after each number for accurate reading across day and night. The bezel turns in both directions, allowing a third time zone to be tracked when needed.
The bracelet is one of this reference’s defining features. For the first time, a steel-and-gold GMT is paired with the Jubilee bracelet. Its five-link design combines brushed steel outer links with high-polished yellow gold center links, offering a supple fit and a two-tone look that instantly stands out. The bracelet flows into an Oysterlock safety clasp that follows the same finishing: high-polished gold down the center, brushed steel on the sides. It also houses the Easylink extension system, letting the wearer expand the fit by 5 mm without tools for added comfort throughout the day.
Together, the case and bracelet set the stage for the 126713GRNR’s look, but the dial is where this “Bumblebee” reference really makes its impression.
A Black Dial That Shows Its Character in Every Setting
The dial of the 126713GRNR is finished in glossy black lacquer, giving it a deep reflective surface that contrasts with the markers and hands. The hour markers are large and easy to read: circles, rectangles, and a triangle at 12 o’clock. Each is filled with white Chromalight lume and framed in 18k yellow gold, which adds definition and helps them stand out against the dark dial.
At night, the Chromalight glows a bright blue, covering not just the markers but also the hands. The Mercedes-style hour hand, the minute hand, the triangular tip of the GMT hand, and even the lollipop end of the seconds hand are all filled with lume, ensuring visibility in any lighting.
At 3 o’clock sits the date window, enlarged by the Cyclops lens for quick reading. Around the dial, a fine minute track allows for precise timing.
By keeping the GMT hand in yellow gold instead of a colored accent, Rolex has given this model a unified, understated dial that pairs seamlessly with the grey-and-black bezel. Together, these details make the face of the 126713GRNR both functional and unmistakably Rolex.
The GMT Functions That Keep You on Schedule
Inside the 126713GRNR is the Calibre 3285, a self-winding movement built entirely in-house and fitted with a bidirectional rotor that keeps it charged with every wrist motion. It carries a 70-hour power reserve and is tested to Superlative Chronometer standards, running at –2/+2 seconds per day for accuracy that holds up in daily use.
The movement is equipped with a Chronergy escapement for improved efficiency, a blue Parachrom hairspring that shrugs off magnetic fields, and Paraflex shock absorbers to protect against everyday knocks. Together, these details help the watch maintain steady performance whether you’re at home or traveling.
Functionality is where this GMT-Master II shines. The independent local hour hand lets you adjust to new time zones quickly without stopping the watch, while the 24-hour hand and grey-black Cerachrom bezel work together to track a second and even a third time zone. Add in a water resistance rating of 100 meters, and you have a watch built for reliability across long-haul flights, weekend trips, or everyday wear.
Together, these features combine mechanical precision with practical tools for daily wear and travel. Next up: let’s explore how the watch feels when it’s on your wrist.
Why It Feels Easier to Wear Than You Expect
On the wrist, the 126713GRNR wears comfortably at 40 mm, present on the wrist without being hard to manage. The Jubilee bracelet adds flexibility and contour, so it moves easily with the wrist and avoids the stiffness you sometimes get with Oyster links. The two-tone mix of steel and yellow gold gives a measured shine that stays tasteful in different settings.
The watch has a reassuring presence, yet owners are often surprised that it doesn’t feel much heavier than the all-steel model. At about 12 mm thick, it sits close to the wrist, secure without feeling bulky. That balance makes it just as suitable for long flights as it is for a night out.
Collectors often point out how the yellow gold feels natural here, even for those who typically steer clear of two-tone pieces. It’s this mix of comfort and proportion that gives the Bumblebee its appeal as a daily-wear GMT.
Next, let’s summarize the key details at a glance.
Rolex GMT-Master II 126713GRNR “Bumblebee” – Key Details
| Feature | Description |
| Case | 40 mm Oystersteel and 18 ct yellow gold case, 12 mm thick. Brushed lugs with high-polished sides for contrast. Screw-down crown with Triplock triple waterproofness system. Waterproof to 100 m (330 ft). |
| Bezel | Bidirectional rotatable 24-hour bezel. Two-colour Cerachrom insert in grey and black ceramic with recessed, gold-coated numerals and graduations. |
| Dial | Glossy black dial with large white hour markers bordered in gold, in a mix of circular, rectangular, and triangular shapes. Minute track around the outer edge. |
| Lume | Chromalight display with long-lasting bright blue glow. Applied to hour markers, Mercedes hour hand, minute hand, seconds hand tip, and triangular tip of the GMT hand. |
| Hands | Mercedes-style hour hand, minute hand, seconds hand with luminous tip, and an additional 24-hour hand with luminous triangle for tracking a second time zone. |
| Date | Date display at 3 o’clock, enhanced by the Cyclops magnifier |
| Bracelet | Jubilee bracelet in Oystersteel and 18 ct yellow gold. Five-piece links with brushed steel and high-polished gold center links. Equipped with Oysterlock folding safety clasp and Easylink 5 mm comfort extension link. |
| Movement | Calibre 3285, perpetual mechanical self-winding GMT movement. Precision of -2/+2 sec/day after casing. Features a paramagnetic blue Parachrom hairspring and Paraflex shock absorbers. Power reserve approx. 70 hours. |
| Functions | Centre hour, minute, and seconds hands; 24-hour hand; independent quickset of the local hour hand; second time zone display; instantaneous date; stop-seconds for precise time setting. |
| On-Wrist Feel | Balanced at 40 mm and around 12 mm thick. Comfortable weight with Jubilee bracelet flexibility, making it easy for all-day wear. The two-tone steel and gold brings subtle shine, while still feeling secure and practical for both travel and evening use. |
A Two-Tone That Even Gold-Shy Collectors Warm Up To
The Rolex Bumblebee is one of those watches that changes your mind once you wear it. The balance of steel and yellow gold is convincing, and paired with the comfort of the Jubilee, it is easy to forget you’re wearing a two-tone at all. Collectors mention that it shifts smoothly from the airport to a night out, which makes it more useful than they first thought. That kind of adaptability is what makes the 126713GRNR a piece that lingers in your thoughts, and sometimes that’s the best sign it’s the right choice.
