The DEWALT DW03050 165" Laser Distance Measurer has the ability to calculate area and volume, making job estimates quick & easy with automatic calculations. The indirect height measurement uses Pythagoras to measure distances even when point A and/or point B isn"t accessible for linear measurement. A memory unit stores last 5 measurements and the 2-Line backlit display helps improve screen visibility in both dim and bright conditions. This unit has a durable design featuring an over-molded housing, 6 ft (2m) drop tested and IP65 water/debris resistance. Operating range up to 165ft/Accuracy: +/- 1/16" (1.5mm). Uses (2) AAA batteries, included.