
Squale 1521 · Ref. SQUALE 1521 · 20mm lug · 42mm case
At a Glance
| # | Best For | Strap | Material | Thickness |
|---|---|---|---|---|
| 1 | Overall / First Purchase | Dark Brown Saffiano Stitchless Strap | Saffiano Calfskin | 2.2mm |
| 2 | Dressy / Formal | Glossy Lilac Crocodile Signature Strap | Crocodile | 4.5–2.2mm |
| 3 | Everyday / Casual | Grigio Pueblo Slim Strap | Pueblo Calfskin | 2.2mm |
| 4 | Minimalist / Refined | Black Shell Cordovan Slim Strap | Shell Cordovan | 2.2mm |
| 5 | Casual / Relaxed | Grey Rubberised Leather (Togo) Signature Strap | Togo Leather (Rubberised) | 4.5–2.2mm |
| 6 | Active / Sporty | Orange Tropical CTS Rubber Strap | FKM Rubber (Tropical) | 4.0–3.3mm |
| 7 | Comfort / Wildcard | Black Hook Strap [kollokium x Delugs] | Fabric | 1.3mm |
Squale has a way of surprising you with how much watch you get. The 1521 (ref. SQUALE 1521) is a case in point. The finishing and attention to detail speak for themselves. A 20mm lug width and that unmistakable character make this watch a natural platform for strap changes.
The case measures 42mm with a thickness of ~13mm (including crystal) — proportions that sit comfortably on most wrists without dominating them. It strikes that balance between presence and wearability that makes it suited to almost any strap.
Here are my 7 picks — and why each one works.
Quick Specs
| Case diameter | 42mm |
| Lug width | 20mm |
| Lug-to-lug | ~48mm |
| Case thickness | ~13mm (including crystal) |
| Water resistance | 500m / 50 ATM |
| Crystal | |
| Case material | Stainless steel (polished) |
| Movement |
The 20mm lug width means your options are curated but well-covered. Already know what you're looking for? Browse all Squale 1521-compatible straps on the Strap Finder →
1. Best Overall — Dark Brown Saffiano Stitchless Strap

If you're buying your first aftermarket strap for the Squale 1521, this is where I'd start.
The Dark Brown Saffiano Stitchless Strap uses saffiano leather — that signature cross-hatch embossed pattern you see on high-end bags and accessories. It is remarkably scratch-resistant and handles moisture better than most leathers, which makes it one of the most practical premium options you can put on a watch. At 2.2mm thick, it balances presence and wearability nicely.

On the Squale 1521, this strap preserves the watch's go-anywhere character. The 42mm case at ~13mm (including crystal) thick pairs naturally with the padded construction without creating any imbalance on the wrist.
Once you see it on the wrist, it just clicks.
The range goes deeper if you want to explore:
- Black Saffiano Stitchless Strap
- Caramel Saffiano Stitchless Strap
- Cream Saffiano Stitchless Strap
- Navy Saffiano Stitchless Strap
2. Best Dressy — Glossy Lilac Crocodile Signature Strap

When you need to dress the Squale 1521 up, this is the strap that delivers.
The Glossy Lilac Crocodile Signature Strap is made from genuine crocodile leather with a distinctive scale pattern that no embossed leather can replicate. The texture adds visual depth and character that works equally well with a suit or a smart-casual outfit. At 4.5–2.2mm thick, it balances presence and wearability nicely.

On the Squale 1521, this strap preserves the watch's go-anywhere character. The 42mm case at ~13mm (including crystal) thick pairs naturally with the padded construction without creating any imbalance on the wrist.
Once you see it on the wrist, it just clicks.
The range goes deeper if you want to explore:
- Glossy Caramel Crocodile Signature Strap
- Glossy Emerald Crocodile Signature Strap
- Glossy Lagoon Blue Crocodile Signature Strap
- Glossy Taupe Brown Crocodile Signature Strap
3. Best Everyday — Grigio Pueblo Slim Strap

An everyday strap needs to be comfortable from the jump and work with most of what you wear.
The Grigio Pueblo Slim Strap features Buttero leather from the Walpier tannery in Italy. This vegetable-tanned leather develops one of the most beautiful patinas in watchmaking — scratches blend into the surface and the colour deepens over time. If you enjoy watching your strap age gracefully, this is the one. At 2.2mm thick, it balances presence and wearability nicely.

On the Squale 1521, this strap preserves the watch's go-anywhere character. The 42mm case at ~13mm (including crystal) thick pairs naturally with the padded construction without creating any imbalance on the wrist.
A combination that's greater than the sum of its parts.
Worth a look in other colourways:
- Dark Brown Pueblo Slim Strap
- Navy Pueblo Slim Strap
- Natural Pueblo Slim Strap
- Cognac Pueblo Slim Strap
4. Best Minimalist — Black Shell Cordovan Slim Strap

Strip away the unnecessary and what's left is pure design. That's this strap.
The Black Shell Cordovan Slim Strap is crafted from premium materials with careful attention to detail and construction quality. At 2.2mm thick, it balances presence and wearability nicely.

The Squale 1521's 42mm case is ideally proportioned for this strap. Whether you are wearing it casually or dressing it up, the combination feels intentional. It is the kind of pairing where both the watch and strap look better together than apart.
Alternatives in the same family:
- Navy Shell Cordovan Slim Strap
- Cognac Shell Cordovan Slim Strap
- Natural Shell Cordovan Slim Strap
- Green Shell Cordovan Slim Strap
5. Best Casual — Grey Rubberised Leather (Togo) Signature Strap

Not every strap needs to make a statement. Sometimes relaxed is the right move.
The Grey Rubberised Leather (Togo) Signature Strap uses rubberised leather — a material that blends the look and feel of leather with the water resistance and durability of rubber. The smooth finish is clean and modern, and the pastel colour options add a playful element to otherwise serious watches. At 4.5–2.2mm thick, it balances presence and wearability nicely.

What makes this pairing work on the Squale 1521 is the contrast — the refined case finishing against the texture creates visual interest without conflict. With a 42mm case, the proportions stay balanced.
Other colours worth considering:
- Black Rubberised Leather (Togo) Signature Strap
- Navy Rubberised Leather (Togo) Signature Strap
- Colibri Rubberised Leather (Togo) Signature Strap
- Hunter Green Rubberised Leather (Togo) Signature Strap
6. Best Sporty — Orange Tropical CTS Rubber Strap

A sportier option that brings comfort and durability without sacrificing style.
The Orange Tropical CTS Rubber Strap is made from FKM rubber — a high-performance elastomer that resists chemicals, heat, and ageing. Unlike silicone, it does not attract dust or lint. Cut-to-size construction means you trim it to your exact wrist measurement — no leftover tail, no keepers. At 4.0–3.3mm thick, it balances presence and wearability nicely.

What makes this pairing work on the Squale 1521 is the contrast — the refined case finishing against the texture creates visual interest without conflict. With a 42mm case, the proportions stay balanced.
It's the kind of pairing that makes you wonder why you didn't try it sooner.
Other colours worth considering:
7. The Wildcard — Black Hook Strap [kollokium x Delugs]
![Black Hook Strap [kollokium x Delugs] on Squale 1521](https://cdn.shopify.com/s/files/1/0054/9040/9585/files/20250919-A7405356.jpg?v=1761298651&width=800)
Not the obvious choice, but sometimes the unexpected pairing is the best one.
The Black Hook Strap [kollokium x Delugs] is crafted from premium materials with careful attention to detail and construction quality. At 1.3mm thick, it balances presence and wearability nicely.
![Black Hook Strap [kollokium x Delugs]](https://cdn.shopify.com/s/files/1/0054/9040/9585/files/Kollokium_straps_Black_1.jpg?v=1761298651)
Paired with the Squale 1521's distinctive dial, this strap adds a layer of personality that the factory option does not offer. The ~13mm (including crystal) case thickness means a padded strap like this one feels proportional and substantial.
It's the kind of pairing that makes you wonder why you didn't try it sooner.
Other colours worth considering:
- Warm Grey Hook Strap [kollokium x Delugs]
- Anthracite Hook Strap [kollokium x Delugs]
- Khaki-Green Hook Strap [kollokium x Delugs]
- Orange Hook Strap [kollokium x Delugs]
A Note on Buckle Colour
Quick but important: always match your buckle to your case. The Squale 1521's Stainless steel (polished) case calls for a silver (brushed or polished) buckle. All Delugs leather straps ship with a pin buckle and can be upgraded to a Spring Deployant Clasp for extra security and convenience. All Delugs straps come with quick-release spring bars pre-installed, so swapping straps takes seconds.
How to Change the Strap on Your Squale 1521
Swapping straps on the Squale 1521 is one of the easiest upgrades you can make — and with Delugs straps, you don't even need a tool.
If your Squale 1521 came on a bracelet, you'll first need to remove it. The easiest way to do this at home is with a Bracelet Removal Tool, which lets you compress the spring bars without risking scratches to the lugs or caseback. Once the bracelet is off, you can slide your new Delugs strap straight in.

All Delugs straps come with quick-release spring bars already pre-installed, so changing straps is completely tool-free. Here's how:
- Prepare your workspace. Lay the watch face-down on a soft cloth or microfiber pad to protect the caseback from scratches.
- Release the spring bar. Locate the small lever on the quick-release spring bar. Pull it back with your fingernail or fingertip to compress the bar.
- Remove the strap. While holding the lever, angle the strap out from between the lugs. Repeat for the other side.
- Insert the new strap. Slide one end of the spring bar into the lug hole. Pull the lever on the quick-release spring bar knob, guide the entire spring bar into the opposite lug hole, and then release the knob. You should hear a small click when the spring bar extends and seats into the lug hole.
- Check the fit. Give the strap a gentle tug to make sure both spring bars are securely locked in. If there's any play, reseat the spring bar.
The entire process takes under a minute once you get the hang of it — no spring bar tool required. The Squale 1521 uses a standard 20mm lug width, and all Delugs straps in 20mm will fit perfectly.
Frequently Asked Questions
What is the lug width of the Squale SQUALE 1521?
The Squale SQUALE 1521 has a 20mm lug width. While 20mm is less common than 20mm, there is still a strong selection of quality straps available. All Delugs straps are available in 20mm.
What is the reference number for the Squale 1521?
The reference number for the Squale 1521 is SQUALE 1521. You can find this on the caseback of your watch or on the original paperwork. Knowing your reference number helps ensure you get the right lug width when ordering a strap.
Can I use a dressy leather strap on a Squale versatile watch?
The 1521 is one of the most versatile watches in the Squale lineup — it takes both dressy and casual straps equally well. That's part of what makes it such a rewarding watch for strap changes. Don't be afraid to experiment.
Do Delugs straps come with spring bars?
Yes — every Delugs strap comes with quick-release spring bars pre-installed. This means you can change straps by hand in seconds, without needing any tools. The quick-release mechanism uses a small lever that you pull with your fingertip to compress the spring bar.
What is the best strap material for the Squale 1521?
The 1521's versatile nature means it works with almost everything. Start with what matches your most common wearing occasion — rubber or sailcloth for active use, nubuck or waxy leather for everyday, and alligator or saffiano for dressier moments. The Strap Finder makes it easy to browse by material and style.
Does Squale use quick-release spring bars?
Most Squale watches use standard spring bars that require a tool to remove. All Delugs straps come with quick-release spring bars pre-installed, so once you make the switch, future changes are completely tool-free.
Where can I find straps compatible with the Squale SQUALE 1521?
The Squale Strap Finder shows every Delugs strap compatible with the SQUALE 1521, filtered by lug width and style. You can also use the general Strap Finder to browse by brand, collection, and material. If you need help choosing, our team is available 24/7 via live chat.
Finding Your Strap
The beauty of the Squale 1521 is that it rewards experimentation. A dressy alligator for the office, nubuck for the weekend — each strap brings out a different side of the watch.
Use the Squale 1521 Strap Finder to see every compatible strap in one place, filtered to your exact reference. Or if you'd rather explore by feel, the general Squale Strap Finder lets you browse the full lineup and find your match.
Not sure which strap is right for your specific 1521? Our team is available 24/7 via live chat — drop us a message and we'll help you find the perfect match for your watch, wrist size, and style.
About Delugs

Founded in 2018 and headquartered in Singapore, Delugs is dedicated to elevating the experience of watch ownership through the simple yet powerful act of strap changing. We believe that straps are integral to how a timepiece is worn, perceived, and enjoyed. Our mission is to make strap changing a lifestyle — an everyday act of self-expression and versatility.
Delugs is an independent brand with a global community of clients, with a strong online presence and growing physical retail footprint. Our direct-to-consumer focus keeps us closely connected with the watch enthusiast community — fostering conversations, hosting events, and helping shape a more inclusive and expressive culture around watch collecting. We also work closely with watch brands to craft straps that complement their timepieces, bridging the gap between brand and collector, form and function.
Our catalogue spans leather, rubber, and fabric straps, with options for every watch and every occasion. We are committed to craftsmanship and quality, product design and innovation, and outstanding customer service. We offer watch owners the freedom to change straps as easily as changing outfits, and the opportunity to engage more deeply with the watches they love.
Visit our flagship boutique at Raffles Hotel, Singapore →
— Marcus

