The Rolex Submariner 126613LB has one of the most loyal followings in the entire Rolex catalog, and it's easy to see why. Blue sunray dial, blue Cerachrom bezel, and that warm hit of yellow gold on the crown, bezel edge and center links. The "Bluesy" pulls off a trick very few watches manage: it's a proper 300m dive watch that also reads as jewelry.
That's exactly why straps get interesting here. On the two-tone Oyster bracelet, the watch is loud in the best way. Put it on the right rubber strap and it suddenly becomes lighter, more casual, and easier to wear every single day, while the gold accents keep doing their thing. Put it on the wrong strap, and the whole two-tone concept falls apart.
Strap size and fit for the Submariner 126613LB
Let's get the boring-but-critical part out of the way first, because this is where wrong orders happen.
The Submariner 126613LB belongs to the current 41mm case generation, and it uses a 21mm lug width. Not 20mm. The 21mm sizing arrived when Rolex moved the Submariner to 41mm in 2020, and it catches people out constantly because most of the watch world lives at 20mm or 22mm.
On Helvetus product pages, the only thing you need to do is select Submariner 41mm. That's it. Choose that option and the strap is made for your 126613LB's exact case shape and lug geometry, so it sits flush against the case with no gaps. Pick the 40mm option because it "sounds close" and you'll see the mistake the moment the strap goes on.
A quick word on the watch itself
Two-tone Submariners have been part of the lineup since the 1980s, but the 126613LB, introduced in 2020, is the most refined version of the formula yet. The 41mm case actually wears slimmer than the older "Super Case" generation thanks to trimmed-down lugs, and inside sits the caliber 3235 with around 70 hours of power reserve. Blue dial, blue bezel, yellow gold in all the right places.
Collectors love the Bluesy because it refuses to pick a lane. It's sporty enough for the beach and dressed-up enough for dinner, and the blue-and-gold combination has become one of the most recognizable looks Rolex makes. Which is also why the strap you choose matters more than on a plain steel Sub: every color you add has to get along with both the blue and the gold.
Here's what actually works.
Blue: the classic Bluesy move
If there's one strap this watch was born to wear, it's blue: Blue Rolex Submariner Rubber Strap
Matching the strap to the dial and bezel turns the whole watch into one coherent blue statement, and the yellow gold accents suddenly pop twice as hard against it. This is one of the most popular strap choices among 126613LB owners, and once you see it on the wrist, you understand why. It's the pairing people picture when they think "Bluesy on rubber."
It also quietly solves the two-tone dilemma: the watch keeps all of its personality but loses the extra metal on the wrist, so it wears lighter and cooler in warm weather.
Black with Blue LuxLine®: sporty, with the blue tied in
This is the pick for anyone who wants the watch to feel sharper and more athletic: Black and Blue Rolex Submariner Rubber Strap – LuxLine®
The black base calms the gold down, while the blue centerline runs straight through the strap and connects visually with the dial and bezel. It reads intentional rather than flashy, and it's the one I'd point to if you wear the Bluesy as a true daily and want it slightly under the radar without going full black.
The deployant version works with your original Rolex clasp, so the two-tone Oysterlock stays on the wrist — a detail Bluesy owners tend to love, because the gold clasp remains part of the look even on rubber.
Brown: leaning into the gold
Brown is the sleeper pick on this reference: Brown Rolex Submariner Rubber Strap
Instead of playing to the blue, it plays to the yellow gold, and the effect is warmer, richer, and noticeably dressier. On the 126613LB, brown rubber lands somewhere between a sports strap and a leather strap: you keep the water resistance and durability of rubber, but the watch takes on an almost vintage, sun-and-boat-deck character. If your wardrobe runs to earth tones, this combination is genuinely hard to beat.
Black: the stealth option
And then there's black, the strap that works on every Submariner ever made, including this one: Black Rolex Submariner Rubber Strap
On the Bluesy, black does something specific: it turns down the volume. The gold and the blue stop shouting and start whispering, and the watch becomes far easier to wear in settings where a two-tone Rolex on a two-tone bracelet might feel like a lot. If you only buy one strap and want zero risk, black is the answer.
Browse everything for the 126613LB in one place
All four picks above, plus the rest of the color range, live in the Submariner collection, and every strap there is available either as a deployant setup that reuses your original Rolex clasp or with a classic pin buckle: All Rolex Submariner Rubber Straps
Just remember the one rule: select Submariner 41mm, and everything fits your 126613LB perfectly.
Final thoughts
The 126613LB is a watch you buy to enjoy, not to store, and the right rubber strap is what makes that realistic: lighter on the wrist, unbothered by sweat and salt water, and kinder to your gold center links, which stay safe at home while you actually live with the watch.
Helvetus makes the decision easy. Every strap here is designed for a precise fit on this specific Submariner generation, backed by a lifetime warranty, with free worldwide shipping and no import costs at checkout. More than 50,000 customers worldwide have already made the switch. Go blue if you want the signature Bluesy look, brown if you want to surprise people, and black if you want a strap you'll never have to think about again.
