Squale Medium 30ATM, 1515, Men’s Diving Vintage Watch, 1980

Vintage Squale Medium 30 ATM diver from 1980, Men’s quartz ETA 536.121 with date and domed acrylic crystal, offered fully serviced and for sale, a rare and timeless compact tool watch.

Squale Medium 1980 — First impression Ref. 1515

The Squale Medium 30 ATM Ref. 1515 embodies the compact professional diver of the early 1980s: a 36 mm stainless-steel case, high-domed acrylic crystal with exterior cyclops and a black acrylic bezel insert with a luminous pip. The dial carries the period-correct “T SWISS MADE T” legend, confirming tritium lume on the square plots and hands. At 3 o’clock sits a clean date display that suits the watch’s purposeful symmetry. Despite its modest footprint, the watch presents real wrist presence thanks to the tall crystal and graphic minute track. This example remains crisply finished, with the signature Squale shark motif on the dial and the engraved caseback underscoring authentic vintage Swiss dive-watch heritage (Ref. 1515).

Medium 30 ATM — Tritium "T SWISS MADE T" Dial

The matte black field contrasts sharply with applied batons at 12/6/9 and chunky square plots elsewhere, all aged tritium that has mellowed evenly. The printed minute track is fine-lined and highly legible, while the shark motif and stacked “30 ATM / Squale / Medium” script anchor the lower half with unmistakable house identity.

A framed date at 3 keeps the layout balanced beneath the external cyclops. Under oblique light, the domed plexi adds charming distortion, a hallmark of serious vintage tool watches prized by collectors.

Medium 30 ATM Ref. 1515 — Hands

A white sword hour hand pairs with a vivid yellow paddle minute hand, both filled with tritium for period-authentic nighttime reading. The slender central seconds sweeps in one-second quartz steps, adding precision to the composition.

This color/shape contrast was typical of professional divers, allowing instant read-off of elapsed minutes against the bezel—one more nod to functional, collectible Swiss dive design.

Squale Medium Ref. 1515 — Domed Crystal & Acrylic Bezel Stainless-Steel Case

The 36.0 mm stainless-steel case wears compact yet tall, its high-domed plexi delivering depth and warmth that sapphire cannot emulate. A black acrylic (bakelite-style) insert offers bold, fully graduated timing with a lume pip at zero; the unidirectional click is positive and tool-like. Flat, straight lugs maintain a clean silhouette and accept 18 mm straps, making the watch versatile across tropic rubber, leather, and mesh.

The solid screw-down back bears the Squale relief medallion, a reassuring period signature. Combined with the screw-down crown, the architecture supported the model’s rated 30 ATM water-resistance when new—serious diving credibility in a rare mid-size format.

Medium 30 ATM Ref. 1515 — Crown

The finely knurled screw-down crown sits at 3 o’clock, seating flush into the case flank without crown guards for a classic tool-watch stance. Operation is crisp for time and quick-date setting.

Based on form and fit, it appears period-correct and likely original to the watch, consistent with surviving 1515 examples from the early 1980s.

Squale Medium — Milanese Bracelet

This piece is fitted with a stainless-steel Milanese (mesh) bracelet featuring a sliding clasp for tailored sizing. The supple weave complements the compact case and reinforces the watch’s functional-yet-elegant character.

While many 1515s were retailed on tropic rubber, a fine mesh is a period-accurate alternative that enhances comfort and airflow during warm-weather wear.

Movement — ETA 536.121 Quartz, Swiss-made Reliability

Powering this Ref. 1515 is the Swiss ETA 536.121 quartz movement, a robust early-1980s calibre used by multiple professional-grade divers. The calibre offers central hours, minutes, sweeping seconds in one-second steps, and a quick-set date. Operating frequency is the standard 32,768 Hz with efficient integrated circuitry for accuracy and low consumption.

Period documentation and parts listings place the 536.121 among the serviceable ESA/ETA families of the era, typically configured with date or day-date and using commonly available silver-oxide cells. In practical terms, it’s a dependable, easily maintained engine—ideal for collectors who value vintage Swiss watchmaking with modern precision.

Heritage of the Squale Medium in the Compact Diver Era

Squale supplied and produced professional dive cases for numerous brands before advancing its own line; the Medium 30 ATM occupies a distinct niche as a mid-size professional diver. In the late 1970s and early 1980s, brands experimented with sizing and acrylic components that improved legibility under water while keeping weight low—this 36 mm format is emblematic of that period.

The tritium-lume architecture, external cyclops and acrylic bezel insert are design cues that enthusiasts now associate with authentic tool-watch intent. Ref. 1515 pieces, especially well-preserved examples with even lume and sharp case geometry, have become sought-after entries into serious vintage Swiss dive collecting.

Squale Medium — 12-Month Warranty, Worldwide Shipping & Verified Originality

Fresh from a full service and function test, this Squale Medium operates correctly through all settings. Case, dial, hands, bezel and crystal present as original components, with honest light wear commensurate with age and careful use. The mesh bracelet is an appropriate period style and suits a wide range of wrist sizes.

We provide a 12-month warranty on timekeeping and movement operation and ship worldwide with careful, insured packing. Explore dive classics on our Diving Vintage Watch curation with 1980 acrylic bezels.