Canon Business/Financial Calculator 10-digit profit margin calculator offers a dual power adjustable tilt and tax and business calculation functions. Includes vinyl wallet protective case. Functions include profit margin calculation, tax calculation, sign change, square root, cost/sell/margin and memory calculation. Solar powered and battery powered so it never lets you down whatever the light conditions. The auto power-off function switches the handheld calculator off in seven minutes when not in use. Calculator weighs 2.9 oz.