With a clinometer for measuring the angle of a slope and an adjustable declination scale the DT 420 has more features than most compasses. The clinometer is useful in snowy mountains as the angle of a slope can indicate the possibility of avalanches but is otherwise only of academic interest. Adjusting the needle for declination, done by means of a tiny screw on the back of the compass, means you don’t have to remember to do so when taking bearings. The DT 420 also has a bezel with a chunky edge that’s easy to turn with gloves on, a magnifi er for seeing map details and anti-slip pads to keep it on a map. There’s a 1:50,000 romer but not a 1:25,000 one. The compass is quite long but as the base plate is tapered acutely at the bezel end the actual straight edge for taking map bearings isn’t as long as on some overall shorter compasses.