Could be one of these: https://ruumur.com/products/mph96?variant=44023976296693

or one of these: https://solgaard.co/products/transatlantic-heyerdahl

It looks like a TISSOT Tachymeter 1853 Chronograph, but, I don’t think I’ve ever seen this model with a day feature!

Grandpa or Grandmaster?

This is what I could find: https://vflwatches.com/eng/product/cushion-case-chrono/

Thanks!! :) Vostok are superb watches, they have their quirks but for a 31 Jewel automatic that people have pressure tested (on YouTube) to 600M for around £100, I picked mine up for £65, you really can’t go wrong.

Vostok Amphibia 090486

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