Indirect height measurement uses Pythagoras to measure distances even when point A and/or point B isn’t accessible for linear measurement. The laser distance measure features a memory unit that stores the last 5 measurements, and a 2-Line backlit display helps improve screen visibility in both dim and bright conditions. It has a durable design with overmoulded housing, which has been 6 ft (2m) drop tested, and is IP65 water/debris resistant. Specification: Accuracy: ±1.5mm. Operating Range: 50m (165ft). Power: 2 x 1.5V LR03 (AAA) batteries (supplied).