Gemini-20 --) Weighs up to 20 grams in 0.001 gram increments ~ Includes carrying case with tweezers, tray and calibration weight * Gemini-20 --) The flip-down shield protects the delicate weighing surface ~ Powered by 2 AAA batteries (included) * Gemini-20 --) Backed by a powerful 10 year warranty * Calibration Weight Kit --) Class: OIML Class M2 ~ Gram Weights: 1 by 50g, 2 by 20g, 1 by 10g, 1 by 5g, 1 by 2g, 1 by 1g * Calibration Weight Kit --) Case dimension: 4.6 by 3-1.2 by 1.7-inch ~ Milligram Weights: 1 by 500mg, 1 by 200mg, 1 by 100mg, 1 by 50mg, 2 by 20mg, 1 by 10mg