For years, the watch-collecting corners of the internet have echoed with the same tragic lament: “The Tudor Black Bay Chrono is too big! It’s too thick! The sides are too flat!”

Honestly, the complaining always cracks me up. I wear the 41mm Black Bay Chrono regularly, and as a woman who supposedly falls into the “needs a smaller watch” demographic, I’ve never once felt like I was lugging around a grandfather clock on my wrist. I think the 41mm wears beautifully. But apparently, enough guys shed tears in the comments sections over those few extra millimeters that Tudor finally decided to pass out the tissues and downsize. 

Let’s talk about the yellow elephant in the room.

Enter the Tudor Black Bay Chrono 39 (M79310N-0001).
If you’re going to shrink a watch, you might as well make it loud enough that people still notice it. Tudor absolutely nailed the visual impact here.

The watch has quickly earned the “Bumblebee” nickname thanks to its vibrant matte yellow dial heavily contrasted by two black snailed sub-counters.

Complete with Tudor’s signature lumed Snowflake hands, a domed sapphire crystal, and a black anodized aluminum tachymeter bezel, it walks a perfect line between vintage motorsport heritage and modern swagger.

While I will defend the bold, chunky stance of the 41mm all day long, I have to give credit where credit is due, the engineering on the 39mm case is undeniably impressive.

Tudor didn’t just shave 2mm off the width; they completely re-proportioned the case. The new 39mm version clocks in at just 13.1mm thick with a compact 47mm lug-to-lug. For a mechanical, automatic chronograph, getting the thickness down to 13.1mm is a massive technical achievement.  

Despite the diet, it still boasts the same heavy-hitting specs we love in the larger model. Inside beats the Manufacture Calibre MT5813, an automatic COSC-certified chronometer movement developed with architectural roots tied to Breitling’s B01. 

The Bracelet Upgrade We All Wanted

As if the new sizing and dial weren’t enough, Tudor quietly delivered the ultimate crowd-pleaser with the bracelet. 

The 20mm three-link stainless steel bracelet now features completely smooth, polished sides. It cleans up the vintage aesthetic wonderfully.  

 It comes standard with Tudor’s phenomenal “T-fit” rapid-adjustment clasp, meaning you can perfectly size the watch on the fly as your wrist swells during the day. 

The Final Verdict

There is no denying that the Black Bay Chrono 39 M79310N-0001 is a triumph. It takes a historically thick, imposing watch style and packs it into a sleek, highly wearable profile. If you have smaller wrists, or if you just love that high-voltage yellow “Bumblebee” dial, this is an absolute home run.  

But am I trading in my 41mm? Not a chance.

There is a certain charm to a sports watch that feels like a sports watch. The 41mm has a rugged, undeniable wrist presence that I adore. So, while the guys on the internet celebrate their newfound ability to fit a Tudor Chrono under a dress shirt cuff, I’ll be over here, sleeves rolled up, proudly wearing my 41mm.

But if I ever decide I need a pop of yellow in my watch box… I know exactly where to look.

Down below an image with me wearing my Black Bay panda, to mention that I have a wrist of 6.5 inch.

What’s your take: are you a “go big or go home” 41mm devotee, or are you ready to embrace the sleek precision of the 39mm?