2026-05-31
Best Watch Straps for the Squale 1521
Best Watch Straps for the Squale 1521
The Squale 1521 is the most historically grounded watch in the Squale range — and one of the most historically grounded dive watches available at any price. The "1521" designation references the year Magellan's expedition completed the first circumnavigation of the Earth. The case design references the professional dive instruments Squale produced in the 1960s and 1970s, when the company supplied cases to Tag Heuer, Doxa, Blancpain and others — and when the Italian Navy's Comsubin diving corps wore Squale on their wrists during operations.
The 1521 is not an homage to another brand's design. It is Squale's own heritage, reissued and refined. The 42mm case with its polished or blasted 316L stainless steel, cushion-shaped profile, and unidirectional bezel has its roots in Squale's own case-making history. The 500m water resistance — five times the minimum for recreational diving — reflects the professional brief the original watches were built for. The Sellita SW200-1 in Elaboré grade runs at 28,800vph with approximately 38-40 hours of power reserve.
The 1521 family is the most extensive in the Squale range. Classic rubber and bracelet variants in multiple dial colours. The Marina Militare — an explicitly military-specification variant with brushed case finish and khaki or olive dial. The Militaire with its tool-watch aesthetic. The Bronze — a bronze case variant that develops a patina specific to the owner's skin chemistry and environment. The PVD black coated variant. The Ocean blasted. All share the same 42mm case architecture, the same 20mm lug width, the same 48mm lug-to-lug.
Squale 1521 Strap Size
The Squale 1521 uses 20mm watch straps lugs — confirmed directly by Squale's own official website across all 1521 variants ("Lug width - 20 mm"). 42mm case, 12.5mm thick (14mm on Bronze), 48mm lug-to-lug.
1521 Classic (rubber or bracelet, all dial colours) — 20mm watch straps. 1521 Marina Militare — 20mm watch straps. 1521 Militaire (rubber or bracelet) — 20mm watch straps. 1521 Blue/Black Blasted (rubber or bracelet) — 20mm watch straps. 1521 Bronze — 20mm watch straps. 1521 PVD — 20mm watch straps. 1521 Ocean — 20mm watch straps. All 1521 variants — 20mm watch straps.
The 1521 Variant Logic — Strap Priorities by Model
Classic (polished steel, multiple dial colours): The most versatile 1521. Any strap material suits the polished case. Warm brown leather creates maximum contrast against the cool polished steel. Tropical rubber references the professional dive watch era.
Marina Militare (brushed case, khaki/olive dial): The most specifically military-specification 1521. Olive and khaki nylon are the most historically coherent strap choices — the brushed case and military dial demand operational fabric. Canvas is the most authentic single material choice.
Militaire (polished case, military-influenced dial): Between the Classic and Marina Militare in character. Nylon and leather both suit it well.
Blasted (bead-blasted matte steel): The most tool-watch-oriented finish. Rubber and nylon suit the matte case most naturally. Brown leather creates an unexpected and characterful contrast — warm leather on matte steel.
Bronze: The most distinctive 1521. Bronze develops a patina specific to the owner — no two Bronze 1521s look the same after six months of wear. Warm brown leather is the most tonally coherent strap for a bronze case — warm metal against warm leather creates a unified palette. Dark rubber suits it for active use. The Bronze is 14mm thick — flat leather at 2-2.5mm is ideal.
PVD Black: The darkest 1521. All-black case suits black rubber or nylon for a unified stealth combination. Brown leather creates the most striking warm contrast against the black case.
Best Rubber Straps for the Squale 1521
Squale ships all 1521 rubber variants on their own rubber strap as standard — the brand's primary material validation.
Tropical style FKM in black at 20mm watch straps — the most celebrated 1521 rubber combination. The vintage basket-weave and honeycomb patterns reference the exact professional dive watch culture the 1521 was born in. The 1521's own heritage — Italian Navy, professional diving corps, Squale's 1960s case-making legacy — is a tropical rubber culture. Black tropical FKM on the 1521 is historically coherent rather than merely decorative.
Brown tropical FKM at 20mm watch straps — particularly effective on the Classic with blue or black dial. Warm brown tropical rubber references the aged rubber of original 1960s professional dive watches — the patina of genuinely used equipment.
Classic FKM rubber in black at 20mm watch straps — the most practical active upgrade. At 500m water resistance, the 1521 genuinely demands a waterproof strap.
Blue FKM rubber at 20mm watch straps — for the Blue Blasted variant. Following Squale's own factory blue rubber choice.
Best Nylon Straps for the Squale 1521
Single-pass nylon — Original at 20mm watch straps with the CNS solid buckle. Most appropriate 1521 colourways by variant:
Classic (all colours): Black, olive, navy, Admiralty Grey, black and grey.
Marina Militare: Olive and khaki are the only appropriate choices — the military specification brief demands military fabric colours. Anything else contradicts the watch's own identity.
Militaire: Olive, black, Admiralty Grey — operational fabric colours.
Blasted: Black or olive for the most tool-watch coherent combination.
PVD Black: Black only — a monochrome combination that suits the PVD case's own identity.
Bronze: Olive or khaki — warm earth tones against the warm bronze case.
Marine Nationale elastic at 20mm watch straps — the most comfortable 1521 daily wear option. The French Navy combat swimmer heritage connects directly to the Italian Navy's Comsubin diving corps that wore Squale watches. Navy or black.
RAF single-pass nylon at 20mm watch straps — for the most specifically European military dive heritage combination.
Canvas at 20mm watch straps in olive — the most specifically appropriate fabric for the Marina Militare. The Italian Navy's equipment culture is a canvas culture — canvas on the Marina Militare is historically coherent.
Paratrooper elastic at 20mm watch straps — the most comfortable daily option.
Best Leather Straps for the Squale 1521
Leather on the 1521 creates one of the most satisfying transformations in the professional dive watch category. The 42mm case and 12.5mm thickness make it proportionally well-suited to moderately padded leather — the case has enough presence to carry a substantial strap without being overwhelmed.
Leather watch straps in dark brown at 20mm watch straps — the most celebrated 1521 leather combination. Warm brown against the polished steel case creates the warm-cool contrast that reveals the 1521's character as a professional instrument worn off-duty. Multiple independent reviewers identify brown leather as the transformation that most reveals the 1521's versatility. On the Bronze variant, dark brown leather creates a warm, tonally unified combination — bronze and brown leather inhabit the same warm temperature range.
Leather watch straps in black at 20mm watch straps — the most formally correct combination. Particularly appropriate for the Classic and PVD variants in formal contexts.
Leather watch straps in tan suede at 20mm watch straps — the most relaxed leather option. Warm tan suits the Bronze and Classic variants for smart-casual wear.
Leather watch straps in dark brown suede at 20mm watch straps — for everyday smart-casual contexts.
Leather watch straps in navy at 20mm watch straps — for the blue dial Classic variants. Navy leather creates tonal coherence between strap and dial.
Thickness note: The Classic and most 1521 variants are 12.5mm thick. Moderately padded leather at 3-4mm suits the case's presence proportionally. The Bronze at 14mm can carry slightly thicker leather without imbalance.
The Marina Militare — A Specific Note
The 1521 Marina Militare deserves specific attention because it is the most directly historically connected Squale reference available. "Marina Militare" is the Italian Navy — the same organisation whose Comsubin combat diving corps wore Squale watches during operations in the 1960s and 1970s. The Marina Militare 1521 has a brushed case finish, a khaki or olive dial with military-specification typography, and SuperLuminova lume that prioritises function over decoration.
The Marina Militare is the only 1521 variant where strap choice carries genuine historical obligation. Olive canvas, olive nylon, khaki nylon, or Marine Nationale elastic in navy are the correct choices. Brown leather is the most appropriate off-duty option. Anything else — bright coloured nylon, decorative fabric — contradicts the watch's identity.
The Squale Cluster
Squale Sub-37 Legend — 19mm watch straps. The compact vintage diver.
Squale Sub-39 — 22mm watch straps. The contemporary Swiss diver.
Squale 1521 — 20mm watch straps. The flagship professional diver.
Recommended Combinations
Most historically coherent — black tropical FKM at 20mm watch straps — vintage rubber on the Italian Navy diver.
Most warm vintage — brown tropical FKM at 20mm watch straps — aged rubber on the professional dive watch.
Most celebrated leather — leather watch straps in dark brown at 20mm watch straps — warm leather on the professional instrument.
Bronze most coherent — leather watch straps in dark brown at 20mm watch straps — warm leather on warm bronze.
Marina Militare most authentic — olive canvas at 20mm watch straps — Italian Navy operational fabric.
Most comfortable daily — Marine Nationale elastic at 20mm watch straps.
PVD most coherent — black single-pass nylon at 20mm watch straps — unified black combination.
Frequently Asked Questions
What size strap does the Squale 1521 take? 20mm watch straps — confirmed directly by Squale's own official website across every 1521 variant including Classic, Marina Militare, Militaire, Blasted, Bronze, PVD, and Ocean.
What is the best strap for the Squale 1521? Black tropical style FKM at 20mm watch straps for the most historically coherent active combination — the vintage basket-weave rubber that references the professional dive watch era the 1521 was born in. Dark brown leather for the most celebrated dress-sport transformation.
What is the Squale 1521 Marina Militare? The 1521 Marina Militare is the most directly historically connected Squale reference — "Marina Militare" is the Italian Navy, whose Comsubin combat diving corps wore Squale watches during operations in the 1960s and 1970s. The Marine Militare variant has a brushed case finish, a khaki or olive military-specification dial, and references the exact operational context the original Squale professional dive watches were built for.
Why does the Squale 1521 Bronze develop a patina? Bronze is a copper-tin alloy that reacts with skin oils, moisture, and environmental exposure to develop an oxidisation layer — the patina. Every Bronze 1521 develops a unique patina specific to the owner's skin chemistry, lifestyle, and environment. Some owners develop a deep chocolate brown patina, others a greenish tone. The patina can be polished away but most owners allow it to develop naturally as a record of the watch's use.
What is the difference between the Squale 1521 Classic and the Marina Militare? The Classic has a polished case finish and a range of dial colours including black, blue, and green. The Marina Militare has a brushed case finish and a khaki or olive military-specification dial. Both share the same 42mm case, Sellita SW200-1 movement, 500m water resistance, and 20mm watch straps lug width.
Does the Squale 1521 have 500m water resistance? Yes — all 1521 variants are water resistant to 500m (50 ATM), achieved through the screw-down crown and caseback. This is professional diving specification — five times the minimum for recreational scuba diving.
All CNS straps for the Squale 1521 are available at 20mm watch straps. Standard delivery worldwide. 30-day returns.