American Weigh ZEO-50 Milligram Scale 50g x 0.001g - Black Linearity: 3d Scale Dimensions: 5.9 x 3.8 x 2.5 in Power: 4x AAA (Included) or AC-Adapter (sold separate) Touch-screen Operation Weighing Units g, oz, ozt, dwt, ct, gn Repeatability: 3d 50g x 0.001g (1mg), Adjustable Feet and Bubble Level 10 Year Limited Warranty . You can correct the scale by simply calibrating the scale. The calibration weight comes with the scale.