The Expedition 4 compass is available in a regular version with a 360 degree bezel, and two military versions marked in mils and degrees. The NATO option sports Betalight illumination for night visibility, and this distinguishes it from the standard military and civilian versions, which use luminous markings. The Expedition 4 sits well in the hand and the comprehensive baseplate features pretty much everything a walker or climber could want. There are romer scales for 1:25k, 1:50k and 1:40k, so you can give very accurate 6-figure grid refs with both OS and Harvey’s maps, and the spare space left on the two long edges is equipped with cm and inch markings for measurements.
A magnifying window sits neatly in the front half of the plate to assist in reading map details, and silicone feet on the underside stop it sliding around too much when you place it on a map. In use, the bezel has a good, positive action with just the right amount of resistance, and there are eight north-south lines on the bezel to make lining up with the map a breeze. There’s no declination adjustment, but for most users, the Expedition 4 really has everything you need, and it comes in at a sound price too.
Romer scales 1:50k, 1:25k, 1:40k
Night use luminous markings
Map magnifier yes
Declination adjustment no
Sighting options none
The Silva Expedition 4 - 360 compass is best for ease of use.
First published in Trail magazine November 2011