u/Mammoth-Ratio4493

Can anyone tell me more about this model?

I can’t find much information online about the specs, and I also haven’t been able to find another version with a red dial.

The caseback appears to say reference 6309-602A, although I’m not 100% sure.

It’s currently listed on my local “eBay” equivalent, and I’m considering buying it just for fun. Before doing so, I wanted to check whether it’s original, whether the red dial might be factory or aftermarket, and whether it’s worth picking up. Thanks!