With this water- and dust-resistant calculator, there’s no need to worry about exposure to water, dust or grime. It is recommended for use even at open-air markets, street stalls and other outdoor businesses and at shops that sell fresh food. 12 digits, Tax calculation (Automatic calculation of price plus tax, price less tax, selling price, tax amount, and margin amount.). Cost/Sell/Margin (Calculate the cost, selling price or margin of profit on an item, given the other two values). Two-way power (Solar + Battery: Solar powered when light is sufficient, battery powered when light is insufficient). Function command signs (A symbol (+, -, ×, ÷) on the display indicates the status of operation you are currently performing). Key rollover (Key operations are stored in a buffer, so nothing is lost even during high-speed input). Large display (Large, easy-to-read display). Plastic keys (Designed and engineered for easy operation). Dimensions (L × W × H) : 187.5 × 139 × 34 mm.