Seiko Prospex HBB004K & HBB003K Review | Sunset Orange vs Golden Hour

Some limited editions make you hunt for the differences. 

Not these two. 

The Seiko Prospex HBB004K Sunset Orange and HBB003K Golden Hour take the same automatic dive-watch formula and turn the colour right up. One gets a textured orange dial. The other goes full yellow. 

Both are Asia-Pacific Limited Editions, with just 2,500 pieces of each available worldwide. 

And really, that's the decision here. Orange or yellow? 

Quick Take

• 2,500 pieces worldwide per model
• 41.7mm stainless-steel case
• 12.3mm thick
• Around 170g
• Automatic Seiko Calibre 4R35
• Approx. 41-hour power reserve
• 200m water resistance
• Hardlex glass
• One-way rotating bezel

• Screw-down crown
• Stainless-steel bracelet
• LumiBrite hands and hour markers

So, What Makes Them Different? 

The dial. That's pretty much the whole argument. 

The Seiko's HBB004K Sunset Orange has a sand-textured orange dial inspired by golden sunsets around Asia-Pacific coastal resorts. A black rotating bezel sits around it, representing the transition from day into night. 

Then there's the HBB003K Golden Hour. 

Yellow is a much bigger commitment. 

If you want something colourful but still relatively easy to work into regular wear, I'd lean orange. If you're buying a limited edition because you want it to look obviously different, the yellow is much harder to ignore. 

Neither is shy, which is exactly the point.

Dial & Design: This Is Where the Fun Is 

The sand-textured finish is what gives both dials their character. A flat orange or yellow could’ve felt a bit one-note, but the texture adds extra depth and gives the colour more going on visually. 

Both watches pair those bright dials with a black one-way rotating dive bezel, which gives the design some contrast and stops the colour from taking over completely. 

You also get LumiBrite on the hands and hour markers for visibility in low light, plus a date window for a bit of everyday practicality. 

The HBB004K feels warmer and a little more relaxed. The HBB003K is louder, brighter and, to my eye, looks more obviously like the special-edition option. 

Same basic layout. Very different personality.

What About the Size? 

Both watches measure 41.7mm across and 12.3mm thick. 

That's a useful middle ground for a modern dive watch. There's enough case there to give the bright dial some presence without pushing the diameter into genuinely huge territory. 

Weight is around 170g on the stainless-steel bracelet. 

So no, this isn't pretending to be a featherweight watch. There's a decent amount of steel here. 

The case also gets a screw-down crown and 200 metres of water resistance, keeping the colourful design backed up by proper Prospex dive-watch specifications. 

Inside: Seiko's 4R35 Automatic 

Both models run the same Calibre 4R35 automatic movement. 

Automatic simply means the movement winds through the motion of the watch while it's on your wrist. 

You get approximately 41 hours of power reserve, which is how long the movement can continue running when fully wound and left unworn. 

And that's about as complicated as this comparison gets. 

There's no better movement hiding inside one colour. No upgraded specification if you choose yellow. 

Pick the dial you prefer. 

Hardlex, Steel and the Practical Stuff 

Both watches use Hardlex glass, stainless-steel cases and matching stainless-steel bracelets. 

It’s a fairly straightforward setup, which works in their favour. With orange and yellow dials doing most of the visual heavy lifting, the rest of the watch doesn’t need to compete for attention. 

Underneath the colour, these are still proper automatic Prospex divers with a practical, all-steel build. 

Sunset Orange or Golden Hour?

This is where the choice gets interesting. 

Go HBB004K Sunset Orange if...
You want the more versatile of the two. Orange is still bold, especially with the textured dial and black bezel, but it feels a little easier to wear regularly. 

Go HBB003K Golden Hour if...
You want the watch that makes more of a statement. The yellow dial is louder, more unusual and much less interested in blending in. 

If you’re buying a limited edition because you want something that feels noticeably different, Golden Hour probably makes the stronger case.

Final Verdict 

The Seiko Prospex HBB004K Sunset Orange and HBB003K Golden Hour prove that a limited edition doesn't need a completely different movement or case to feel different. 

Both give you the same 41.7mm stainless-steel case, 4R35 automatic movement, 200m water resistance, rotating bezel and bracelet. 

Then Seiko lets the dial decide everything else. 

Orange is my pick for regular wear. 

Yellow is the one I'd buy if subtlety wasn't invited. 

Simple choice. Fun watches. 

Seiko Prospex Sea Asia-Pacific HBB004K Automatic Limited Edition

$995.00

Inspired by the golden sunsets of Asia-Pacific coastal resorts, the Seiko Prospex Sea Asia-Pacific HBB004K is a vibrant Limited Edition of just 2,500 pieces worldwide. Its bold orange sand-textured dial evokes sunlit beaches and is contrasted by a distinctive black… read more

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Seiko Prospex Sea Asia x Pacific HBB003K Automatic Limited Edition

$995.00

Inspired by the golden sunsets and tranquil nights of Asia-Pacific coastal resorts, the Seiko Prospex Sea Asia x Pacific HBB003K is a striking Limited Edition of just 2,500 pieces worldwide. Its vibrant yellow sand-textured dial is complemented by a bold… read more

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Key Specifications 

Frequently Asked Questions 

Q. What's the main difference between the HBB004K and HBB003K? 

A. Colour. The HBB004K has an orange sand-textured dial, while the HBB003K uses yellow. Their main specifications are otherwise the same. 

Q. Are both Seiko Prospex models limited editions? 

A. Yes. Each Asia-Pacific Limited Edition is restricted to 2,500 pieces worldwide. 

Q. What movement do they use? 

A. Both use Seiko's automatic Calibre 4R35 with approximately 41 hours of power reserve. 

Q. Can you swim with them? 

A. Both are rated to 200 metres of water resistance and have screw-down crowns. 

Q. How big are they? 

A. Both measure 41.7mm across, 12.3mm thick and weigh around 170g. 

Q. Do they glow in the dark? 

A. The hands and hour markers use LumiBrite, Seiko's luminous material for visibility in low-light conditions. 

Q. Which one is easier to wear every day? 

A. The specifications don't decide this one. For me, the orange HBB004K is the easier everyday colour, while the yellow HBB003K makes the stronger statement.