Clear illuminated LCD display with automatic backlightMagnetic baseSimple operation by just 3 buttonsAbsolute & relative measurementZero set to any position to find the relative angle between 2 planesSee-saw figure on the display to show the tilted directionNo Temperature driftAuto power off functionAluminum frameworkHandy easy to carry anywherePre-calibrated at the factoryAccuracy: 0degree and 90degree : 0.1degree , the rest : 0.2degree Resolution: 0.1degree Working Range: 4 x 90degree Power Supply: 2 x AAA battery Working Temperature: 32Fahrenheit to 122Fahrenheit (0 Celsius to 50 Celsius) Working Humidity: less than equal 85%Colour:blackMaterial:plasticSize:about 60 x 60 x 30mmPackage Contents:1 x PT180 Angle ProtractorOnly the above package content, other products are not included.Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.