Hi Samamtha,

It's a yachting stopwatch from the 1960's - you can see it below in the 1962 catalogue. Although the one in the catalogue has a 10 min sub register, whereas yours has a 5 minute.
I believe different minute countdowns were used for different types of yacht racing. I'm no yachting expert - but they countdown as when a yacht race begins there is a sequence - ie. there is a horn that sounds 5 mins to go till the start of the race, so the yachts have to be tacked so that on the second 'go' horn, they are perfectly positioned right on the start line. Each type of race has different sequences.

Was your grandad a yachtsman?

http://www.onthedash.com/Guide/_Catalogs/1963_Catalog/Page19.jpg

Cheers
Stewart

: Hello. I'm posting to see if I can learn some info on a stopwatch I
: found with my deceased grandfather's belongings. I have no idea
: how old it is, but it's a Heuer and it looks very old. The main
: thing that stands out is the numbers count down instead of up,
: and it starts with a 0 instead of a 60. There's no serial number
: that I can find on the outside, and I don't want to force it to
: see what's on the inside. It's still in working order. I would
: appreciate any knowledge anyone can give me about it. Thank you.

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