News · DOXA

DOXA rebuilds the SUB 300 in Grade 5 titanium

The permanent-collection Ti5 keeps the 300-metre specification, COSC movement and unmistakable bezel while reducing weight.

Hen & Mills Editorial · 4 min read · 3 September 2026

• Grade 5 titanium is used for the 42.5mm case, crown and caseback.
• The COSC-certified automatic movement runs at 4Hz with about 38 hours of reserve.
• Standard colours cost AUD5,250, while Whitepearl references cost AUD5,450.

DOXA has taken one of its most recognisable dive watches and rebuilt the shell in Grade 5 titanium. The SUB 300 Ti5 is not a numbered run or a temporary side project. It joins the permanent collection in seven expressions, keeping the familiar 42.5mm cushion-shaped profile while cutting the weight and changing the feel on the wrist.

The important detail sits in the name. DOXA specifies Grade 5 titanium for the case, crown and caseback. The brand describes the material as light, strong and highly resistant to corrosion, with an exceptional strength-to-weight ratio. Those are practical qualities for a dive watch intended to spend long periods on the wrist and in salt water. Here the case measures 42.5mm across, 45mm from lug to lug and 13.4mm thick.

Those dimensions are close enough to the established SUB 300 shape that this should still read as a DOXA first and a materials exercise second. The short length matters more than the nominal diameter, particularly with the broad case and integrated-looking strap junction. A domed, glass-box sapphire crystal provides the vintage contour without returning to acrylic, and receives an anti-reflective treatment.

A familiar instrument in a lighter shell

The patented bezel retains DOXA's concentric scales for depth and dive time. It turns in one direction, as a dive bezel should, and gives the watch its characteristic outer ring of engraved figures. Water resistance is rated to 300 metres. DOXA says all dive-related indications beneath the crystal are coated with Super-LumiNova, while the oversized orange minute hand supports immediate readability.

Inside is a COSC-certified automatic movement. DOXA does not name the base calibre on the product page, but it does give the useful figures: a 4Hz frequency, equal to 28,800 vibrations per hour, and approximately 38 hours of power reserve. The chronometer certification is more meaningful than a guessed movement reference, and it is the claim buyers can actually hold the watch to.

The bracelet question has also been answered decisively. Every SUB 300 Ti5 comes on DOXA's Dive Flex rubber strap, moulded with a woven texture and fitted to match the case. It is a practical way to preserve the weight advantage of titanium rather than handing some of it back with a full metal bracelet. It also makes the watch less visually dense, especially in the saturated Professional orange shown here.

Seven ways to wear the same specification

DOXA offers the Ti5 across the established colour language of the SUB family, with seven expressions that include Whitepearl executions and strap-colour variations. The case, movement and 300-metre water-resistance rating are shared across the range. The Whitepearl versions differ in giving the entire dial a Super-LumiNova coating, as well as carrying a slightly higher price. Buyers are therefore choosing both an expression and, in that instance, a distinct luminous treatment.

The Professional version remains the obvious shorthand for the brand. Its orange dial has a functional history, but on this watch it also provides the strongest contrast against the muted grey titanium. Darker options make the case look more contemporary, while Whitepearl moves the same tool-watch architecture into something much less conventional.

The colour choice also changes how the bezel reads. On the brighter dials, the engraved timing information remains a dark mechanical border around the display. On the darker references, the luminous indications do more of the separating work. The core case, movement and water-resistance specification stays constant, so the useful test is not which version appears most serious in a photograph, but which one remains easiest for its owner to read at a glance.

The appeal of Grade 5 titanium here is more direct than a claim about decorative finishing. Its low mass, strength and corrosion resistance support the SUB 300's working brief, particularly when the watch is worn for a long day around salt water. The material changes the physical experience while the familiar bezel, crown guards and 300-metre rating keep the design anchored as a dive instrument.

There is no attempt to disguise the Ti5 as precious or especially delicate. The crown remains guarded, the bezel remains busy and the dial remains organised around elapsed-time reading. Titanium changes the physical experience without sanding away the design's useful eccentricity.

Price and availability

The DOXA SUB 300 Ti5 is listed for pre-order through the brand's Australian online store as part of the permanent collection. Professional, Sharkhunter, Caribbean and Redcoral references are priced at AUD5,250, while Whitepearl is AUD5,450. The Professional page gave a 9 October 2026 delivery date when checked, while the Whitepearl page gave 9 November 2026.

At that level, the case material, chronometer certification and 300-metre rating do the commercial work. More importantly, they arrive in a watch with a settled identity. The Ti5 does not ask the SUB 300 to become sleeker or more generic. It simply makes the existing object lighter, tougher and easier to wear for a long day near, or under, the water.