Lightweight and simple to use, the A10 compass provides the beginner with all the basics with which to take accurate bearings, adjust for declination, and make calculations on a topo map. 4 x 2.25 inch clear plastic base plate. 2-inch ruler measurement. Rotating dial with 2 degree increments. Operates in temperatures down to -40 degrees fahrenheit. Sapphire jeweled bearing. Liquid filled for steady needle. Individually balanced tungsten steel needle. Adjustable nylon neck cord. Weighs just 1 oz.