Extra Large displayLarger display makes more data easier to read.Two-way power (Solar + Battery)Solar powered when light is sufficient, battery powered when light is insufficient.Key rolloverKey operations are stored in a buffer, so nothing is lost even during high-speed input.Plastic keysDesigned and engineered for easy operation.Cost/Sell/MarginCalculate the cost, selling price, or margin of profit on an item, given the other two values.Tax calculationAutomatic calculation of price plus tax, price less tax, discount, selling price, tax amount, discount amount, and margin amount.Profit margin percent" % " key gives quick access to prices and profits, and also delivers add-ons, discounts, ratios and increase/decrease values.Function command signsA symbol (+, -, ×, ÷) on the display indicates the status of operation you are currently performing.