Seiko Credor references - what’s the difference between 2F70-5380, 6730-5330, and all the similar models?

Hi everyone,

I’ve recently fallen down the rabbit hole of vintage Seiko Credor quartz watches, especially the stunning ones with blue agate dials powered by the ultra-thin 2F70 movement.


While digging around, I’ve come across what seems to be several different references that all look almost identical, which has left me a bit confused - especially as I’m getting ready to buy one myself very soon.


Here’s what I’ve found so far:

🕺 Men’s / unisex models:

• 2F70-5380
• 6730-5330
• 6730-5331

💃 Ladies’ models:

• 2F70-5390
• 6730-5340
• 6730-5341

All of these appear to share:

• A very similar ( identical?) case and integrated bracelet design
• Blue agate stone dials with slight variations in texture or hue
• Slim, elegant profiles typical of Credor dress watche

What I’d love to understand:

• Are these just different case codes for different years, or are there actual differences in dial finishing, build quality, size, etc.?
• Are the 5380 and 5330 exactly the same model under different names? Or is one somehow more desirable?
• And on the ladies’ side, why do we have so many references (5390, 5340, 5341) for what seem to be very similar or even identical models?

This will likely be my next watch purchase (I’m leaning toward the men’s 5380 or 5330), but I’d really like to understand the details before committing - and potentially figure out which reference is the “best” to go for.

If anyone owns one of these, has catalog scans, or simply knows how Seiko/Credor structured their references in that era, I’d be truly grateful for your input!

Thanks a lot in advance 🙏

⬆️ Here a lady 6730-5340


⬆️ Here a men's 2F70-5380




⬆️Here the only one I found with a (very nice) credit buckle. It's a 2F70-5380. All the other ones had plain SS buckles.


⬆️ Here a men's 6730-5331



⬆️ Here a men's 6730-5330

I couldn't agree more on the wrist size issue !
Most listing I saw had very small size compared to my 19cm wrist.
I'm not saying JDM market issued watches are prone to small sized wrists but 😂😂

Anyway I actually pulled the trigger one of them with 20cm length. It also has a very nice credor clasp. I'll just have to get it cleaned by my watchmaker as the part between the crystal and the case has a lot of dirt in it.

I think I paid a fair price for it, fairly 250€

Can't wait to receive it !

And I think you should keep looking If you really like that watch as I saw quite a lot for sale the last few weeks. Check on insta #credor and eBay.

It's the one i sent pictures of. The ref is 2F70-5380 (the men's version). Careful as the 2F70-5390 looks the same but a bit smaller (ladies version). Same diameter I think but different lug to lug.