The Deli W39231B 12-Digit GT Calculator is engineered to meet the diverse computational needs of professionals, students, and home users. Its large LCD screen provides clear and easy-to-read numbers, reducing the likelihood of errors during data entry and review. One of the standout features of this calculator is its 120-step check and correct function. This allows users to review and amend up to 120 previous entries, making it particularly useful for complex calculations where accuracy is paramount. The Grand Total (GT) function further enhances its utility by enabling the accumulation of totals across multiple calculations, streamlining processes that require cumulative summing. The calculator is equipped with dual power sources: solar power for energy efficiency and a battery backup (1 AA battery) to ensure uninterrupted use even in low-light conditions. This dual-power system guarantees that the calculator is always ready for use, regardless of the environment.