Trend DAR/200 200mm Digital Angle Ruler, Internal and External Angle Finder Digital display for precise angles Stainless steel rule with metric/imperial scale, scale length 200mm and 7-Inch Measuring range from 000.0 Degree to 360.0 Degree, with accuracy of 0.3 Degree Rule locking function Easy operation with two press buttons with a Auto-shut off in 6 minutes