The OREVA OR-512 is a versatile 12-digit calculator designed for both professional and personal use. It features a 120-step Check & Correct function, allowing users to review and amend previous calculations for enhanced accuracy. The device is powered by both solar energy and battery, ensuring uninterrupted operation under various lighting conditions. Its large, easy-to-read display and color-coded keyboard facilitate user-friendly navigation. Additionally, the calculator includes an automatic power-down feature to conserve energy when not in use. These attributes make the OR-512 suitable for environments such as offices, homes, showrooms, and educational institutions. Users have praised the OR-512 for its sturdy construction and the convenience of its GST calculation feature, which simplifies tax computations. The calculator’s sleek design and responsive keys have also been highlighted as positive aspects. However, some users have noted that the key layout may require an adjustment period, and a few have reported issues with button responsiveness over time