BlueDot Trading Digital Jewelry Scale, 600 by 0.1gm, Silver 5 different weighing modes -ct= carats, g=grams, oz.=ounces, gn= grain, dwt=pennyweight Minimum Weight Should be 1.0g or more Weighing tray measures 2 1/2" x 3" Power: 2 x AAA batteries Scale has auto shut off after approx. 2 minutes to save battery life