This is an excellent instrument for pinpointing the  line of site when surveying dish placement. Looking through the lens you can sight the elevation and angle just like a rifle scope so there is no guesswork as to placement of a dish and whether or not you will have line of site to the satellite. Very high quality, constructed of solid aluminum. (Be sure and check  out our AF1 Tandem Compass/ Inclinometer. Same professional type tool as the Suunto Tandem, but at a huge savings! )