What time is it? Watches and horology

Was given this recently, it was my Grandfathers, possibly bought in the 60s.
Does anybody know anything about it? Ive had a google, but cant seem to find out very much relating to this specific model/type

I know very little about Certina, but they seem a decent make and well finished. There is a blog on the service of a non auto Certina here

http://watchguy.co.uk/service-certina-kim-23-36/