?Features:
Area， Volume Calculations: Has m2/ft2/m3/ft3 units
Indirect measurement using Pythagoras:Support 2， 3 indirect measurements
Addition/Subtraction: √
Continuous Measurement: √
Min/Max Distance Tracking: √
Display illumination and multi-line display: Max 4 displays
Datum Option: Can choose Front edge or end piece edge as datum
Buzzer indication: √
Backlight Display: White， can auto switch off
Auto Bias Technology: Support for external calibration
Error indicator: Display error code
Data Hold: Auto
History measurement records: 20
Data Clear: √
Battery indicator: High， mid， low
laser Auto. switch-off: after 0.5 min
Auto instrument switch-off: after 3 min
Waterproof: IP54
Laser type: 635nm，﹤1mW， Class II
Battery Life: !#!gt!*!5000 times
Key Life: !#!gt!*!1 million times

Specifications:
Measurement Distance: 0.1m~60m? ± 1.5 mm?? 4 in ~197 ft ± 0.06 in
Measuring units: m，in，ft. 4 types units displays
Battery: AAA 1.5V * 2 (not included)
Color: Red + Gray
Package Size: 21 * 14 * 7cm / 8.3 * 5.5 * 2.8in
Package Weight: 312g / 11oz

Package list:
1 * UNI-T UT391 Laser Distance Meters
1 * English Manual