The FREEMANS Mini Digital Level & Protractor is compact and lightweight. It features a (1) Measuring Range of 4*90° and (2) an Accuracy of ±0.3° / ±0.5%. UNIT CONVERSION: Toggle easily between degree (°) and percentage (%) measurement units. MAGNETIC MEASURING SURFACE: Equipped with magnets for hands free use on metal surfaces. NOTABLE FUNCTIONS include Reference Angle Measurement, or the ability to measure relative to a pre-set angle. The device can easily be calibrated to maintain its accuracy. 1-YEAR WARRANTY CARD. The mini Digital Protractor comes complete with batteries, and an instruction manual (including warranty card). The product is guaranteed for one year against manufacturing defects.