Seestern Sub600T Review – A Daring 200m Diver Homage

The Seestern Sub600T is a diver that leans heavily into geometric case shaping and tactile bezel engineering, echoing the blocky silhouettes of classic 1970s dive watches. At around $120, it sits in the mid-budget diver segment on AliExpress, offering fully modern materials — a sapphire crystal, ceramic bezel insert, and the NH35 movement — combined with a few uncommon touches, including a fully lumed date window and an off-axis dial layout. Rather than aiming for a soft or rounded aesthetic, the Sub600T embraces an angular, stacked, tool-forward identity.

We have reviewed other Seestern watches, mostly homages yet the refinement and bright, long lasting lume are a commonality.

Seestern Sub600T – NH35 Diver Wtach

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Design & Case

The Sub600T measures 40.2 mm in diameter, 13.3 mm thick, and carries a notably long 52.1 mm lug-to-lug. Although the numerical span sounds large, the watch does not wear as oversized as the figure suggests. This is due to the short, sharply sloped lugs, which drop steeply toward the wrist, giving the case a pseudo-integrated look and allowing it to sit securely even on a 6.5-inch wrist.

The case architecture is layered and deliberate. The flat horizontal flanks give it a squared stance, offset by a polished 45° bevel running along the upper case edges. From the side, you see the stacked construction clearly: the brushed lip of the screw-down caseback, the broad midcase flank, and the tall, block-shaped bezel sitting above them. The geometry is more muscular than refined, but consistent with the watch’s tool-oriented intent.

A 6.44 mm screw-down crown is positioned at 4 o’clock, recessed slightly into the case and carrying the Seestern starfish signature. Engagement is quick thanks to a thin stem, and the crown sits well protected without being difficult to access.

Bezel

The bezel is one of the watch’s standout components. It uses a tall, industrial coin-edge grip, with each block divided into four micro-grooved cuts to increase traction. Vertical surfaces are brushed, while the thin steel lip beneath the ceramic insert is polished, adding a small visual break.

Rotation feels tight, evenly resistive, and audible, with a pronounced ratchet and no looseness or wobble. Clicks are consistent across the full rotation, and alignment at twelve is precise. The polished black ceramic insert features white and orange markings, giving clear contrast on the wrist and reinforcing the diver identity.

Bracelet & Clasp

The bracelet uses chunky 3.6 mm-tall links, but each link is only 5 mm long, much shorter than a typical three-link design. This short-link construction gives the bracelet an unexpectedly fluid drape and helps it contour closely around the wrist.

Build is straightforward: push pins rather than screws, with tolerances that show minor gaps on close inspection. Still, articulation is smooth, and wearability is strong across a range of wrist sizes. The bracelet tapers from 20 mm at the lugs to 18 mm at the clasp.

The clasp is a milled, double-pusher fold-over with six micro-adjust holes, giving practical fine-tuning and a sturdy, diver-appropriate feel. On the underside, the milled folding wing reinforces the clasp’s solidity.

The screw-down caseback carries an engraved wave motif and starfish logo, along with the standard etched specifications.

Crystal & Dial

A synthetic sapphire crystal sits nearly flush with the ceramic bezel, rising only slightly above the insert. Beneath it is a brushed stainless-steel rehaut that funnels the eye cleanly toward the dial.

The dial is matte black and organized around clear legibility. Applied indices follow a mixed layout:

• At 6, 9, and 12, Seestern uses five-facet angled indices, giving the dial more physical texture.

• The remaining hours use circular lume plots with orange edging, tying the color scheme to the bezel accents.

The handset follows a direct tool-watch approach: white hour and minute hands for clarity, with an orange-edged minute hand and a white seconds hand featuring a square lume tip.

A defining feature of the Sub600T is the lumed date window at 3 o’clock. The frame is well proportioned, and the date wheel glows in the same blue tone as the indices — an uncommon detail at this price point.

Branding follows an unconventional layout: “Seestern” is placed left-offset between 9 and 10, while “Automatic 200 m” is angled around 4 o’clock, echoing the diagonal line created by the 4 o’clock crown position.

Lume

Lume performance is strong and uniform. The hands, indices, and the loomed date all glow in a bright blue tone, with good initial intensity and steady decline rather than a sudden drop-off. The level is consistent with Seestern’s typical performance in the sub-$150 diver range and gives the watch reliable nighttime readability.

Movement & Crown

Inside is the familiar Seiko NH35 automatic movement, running at 21,600 bph, offering hacking, hand-winding, and about 42 hours of power reserve. It is a predictable workhorse choice for this segment, chosen for reliability rather than novelty.
Combined with the screw-down crown and caseback, the watch achieves 200 m water resistance.

Summary

The Seestern Sub600T takes a distinctly angular, tool-focused path that sets it apart from the more rounded diver designs common on AliExpress. Its geometry, tall bezel, and short-link bracelet give it a visual and tactile identity that feels intentionally rugged. The lumed date window, off-axis dial text, and layered case construction provide additional differentiation.

While the bracelet tolerances and push-pin construction sit within expectations for the price, the overall package is coherent and purposeful. For buyers who appreciate a blocky, 1970s-inspired diver with modern materials and an NH35 movement, the Sub600T delivers a grounded and visually distinctive option in the mid-budget segment.

Specifications Table

Seestern Sub600T – NH35 Diver Wtach

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