In addition to the features of the Silva Expedition 15T, the Silva Expedition 15TDCL compass also has permanent compensation for magnetic declination & a clinometer for inclined angles.
Features: Magnifying mirror & sighting hole at the lower edge of the mirror for the most accurate bearings. Silicon rubber feet for best friction on map when taking bearings. Romer scales of 1:50.000 & 1:25.000 for plotting positions on maps & mm/inch map measuring scales. Built-in magnifying lens & luminous markings for night navigation are other important features for the most demanding users. As recommended by Ray Mears.