For book keeping to education purposes 8-digit, eye-angled upright LCD display prevents overhead glare and eye strain and shows numbers in clear detail, even in dim lighting. Functions include floating decimal point system, extraction of square root, tax calculation, percent, sign change, cost-sell margin and markup to meet a variety of calculating needs. Large keytops and keytop characters prevent miscalculations. Extra-compact size enables simple transport. Dual-power design allows the calculator to charge via batteries or solar power for flexibility. Renewably powered - designed to work without relying on an electric connection or disposable batteries, potentially helping you save money.