PHYLIDA 500M Diver Watch NH35 Automatic Sapphire Steel

Phylida 500M “Deep Diver” Watch – NH35A Automatic | 43.5mm | Sapphire | Helium Escape Valve

Most dive watches are rated for the pool and the shower. The Phylida 500M Deep Diver (Model DE-11) is rated for the ocean floor. At 500 meters / 50 ATM, this is a professional-specification saturation diver with a helium escape valve at 9 o’clock, a TMI NH35A Japanese automatic movement, a double-domed sapphire crystal with anti-reflective coating, and BGW9 blue lume across every hand, index, and bezel pip. The 43.5mm case wears with serious wrist presence and the blue-to-black sunburst gradient dial delivers the visual depth to match the depth rating on the caseback. This is a limited edition release — one of the most technically specified dive watches available at JwlrAddicts at any price.

Browse the full Phylida watches collection and read the Phylida watches guide to see how the 500M compares to the rest of the Phylida lineup.

Built for Saturation Diving — Not Just the Deep End

The helium escape valve is the feature that separates a recreational diver from a professional saturation diver. During saturation diving operations, where divers live and work under pressure for extended periods, helium molecules from breathing gas permeate the watch case. When pressure is rapidly released during decompression, that trapped helium needs somewhere to go — otherwise it can blow the crystal off the case. The Phylida 500M’s helium escape valve at 9 o’clock manages exactly this, venting excess pressure safely during decompression. It is a feature found almost exclusively on watches at significantly higher price points. The screw-down crown and screwback caseback complete the sealing architecture — nothing about the waterproofing on the DE-11 is an afterthought.

Key Features

• TMI NH35A automatic movement — Japanese caliber with hacking, hand-winding, and 41-hour power reserve
• 500M / 50 ATM water resistance — rated for professional saturation diving
• Helium escape valve at 9 o’clock — essential for saturation diving decompression
• Double-domed sapphire crystal — with anti-reflective coating, scratch-resistant
• BGW9 blue lume — long-lasting, bright glow on hands, all indices, and bezel pip
• Unidirectional 60-minute-scale bezel — for elapsed dive time tracking
• Blue-to-black sunburst gradient dial — shifts appearance dramatically in different lighting
• 316L stainless steel case and bracelet — brushed and polished finish, saltwater-resistant
• Screw-down crown and screwback caseback — full sealing integrity
• 43.5mm case diameter — bold, substantial dive watch presence
• Limited edition — not a permanent production model

Specifications

BGW9 Blue Lume — The Professional Standard

BGW9 is a Swiss-manufactured Super-LumiNova formulation that emits blue light in darkness. Compared to the more common green C3 lume, BGW9 charges quickly, emits a cooler blue glow that retains legibility longer at low intensities, and pairs visually with the blue-to-black dial in a way that makes the watch feel coherent between day and night. On the DE-11, BGW9 is applied to the hour and minute hands, the seconds hand tip, all 12 hour indices on the dial, and the bezel pip — ensuring full 360-degree dark-readability in deep-water and night-diving conditions where partial lume coverage is not sufficient.

The NH35A in a Professional Dive Context

The TMI NH35A is a workhorse movement trusted across the enthusiast and professional dive watch market precisely because it is robust, serviceable, and consistent. Its 41-hour power reserve means a watch left in a dive bag overnight still has reserve power when you need it the next morning. Its hacking function means you can coordinate your dive watch to a dive computer or surface timer with second-level precision. Its hand-winding capability means you can bring a stationary watch to full reserve before a dive without relying on wrist motion. For underwater use, these are not luxury features — they are operational requirements.

How the 500M Fits the Phylida Dive Range

The DE-11 is the deepest-rated watch in the Phylida lineup. If you want maximum depth specification in a professional-grade instrument, this is the model. For buyers who want a serious dive watch with less case bulk, the Phylida SE-11 41mm Diver at 200M is the compact alternative at 41mm. For the everyday sport-classic automatic with 100M, the Phylida SE-31 is the 40mm option. For a compact 38mm everyday with 150M and a choice of bold dial colours, the Phylida AQUA AT150 is the lifestyle-oriented choice. For 500M comparison from other serious divers stocked at JwlrAddicts, the SteelDive SD1954 Water Ghost at 300M and Seagull Ocean Star 1207 at 300M represent the closest alternatives at a lower depth rating and lower price point.

Who Is the Phylida 500M For?

Three distinct buyers will find exactly what they need in the DE-11. The working or recreational diver who wants a watch that matches their actual underwater exposure and never requires a second thought about depth limits. The collector who wants a technically complete professional diver — helium valve, BGW9 lume, sapphire, NH35A, 500M — in a limited-edition package that most comparable brands charge hundreds more for. And the bold everyday wearer who wants a 43.5mm diver with a dramatic blue sunburst dial that shifts between deep ocean and midnight black depending on the light — a watch that is genuinely impossible to ignore on the wrist.

Frequently Asked Questions

Is the Phylida 500M suitable for professional saturation diving? Yes. The 500M / 50 ATM rating and helium escape valve are the two defining features of a saturation-rated dive watch. Both are present on the DE-11, making it suitable for professional dive operations where most recreational divers will never push near its limits.

What is the helium escape valve and why does it matter? During saturation diving, helium molecules from breathing mixtures permeate the watch case under sustained pressure. When pressure is released during decompression, a helium escape valve allows that trapped gas to vent safely, preventing the crystal from blowing off the case. It is a feature standard in professional dive watches and rare at this price point.

What movement does the Phylida 500M use? The TMI NH35A — a Japanese automatic caliber with hacking and hand-winding, manufactured by Seiko’s movement division. 41-hour power reserve, no battery required.

What is BGW9 lume? BGW9 is a Swiss-manufactured Super-LumiNova formulation that emits blue light in darkness. It charges quickly, holds its glow longer than standard lume at low brightness, and is the lume of choice for professional dive watch applications.

Is the 43.5mm case too large for everyday wear? The DE-11 is a statement watch — 43.5mm with an 18mm thickness and a 52mm lug-to-lug is substantial by any measure. It suits medium-to-large wrists and will be noticeable on the wrist by design. If you prefer a more compact everyday profile, the SE-31 at 40mm or SE-11 at 41mm are better fits.

Is this a limited edition model? Yes. The Phylida DE-11 500M Deep Diver is a limited edition release and stock availability changes regularly.

Case size: 43.5mm
Thickness: 18mm
Lug to lug: 52mm
Movement: Automatic [NH35A]
Lume: BGW9 Blue lume
Dial window: Double domed sapphire crystal
Bezel & insert: 120 Clicks; unidirectional; lumed ceramic insert
Crown: Screwdown crown
Caseback: Screwback case
Case material: Solid 316L stainless steel
Water-resistant: 50Bar [500M]