When you ask somebody the time, chances are you’re not expecting their reply to go right down to the second. You probably don’t even think twice if they just say ‘nearly quarter past’. So why should your watch need to be accurate to a sixtieth of a minute? That’s the idea behind Optik Instruments’ Horizon (£349). Rather than hands on the face, it has a red line marked on the stainless steel case and a rotating disc that’s divided up into 15-minute segments, with one complete turn representing a full day. Available in six different designs, each one is waterproof to 100m, although if you were thinking of using it to work out how much oxygen’s left in your tank when you go scuba diving, you might want to consider using something a little more accurate.