Mr. Pen simple calculator makes everyday math fast and easy for the office, primary school, the market, and home. 12-digit display — large, easy-to-read numbers with clear visibility from multiple angles. Standard function calculator — perfect for basic numerical calculations anytime you need quick answers. Big, sensitive keys — easy-to-press buttons for smooth, quick data entry. Everyday functions included — add, subtract, multiply, and divide with ease. Percent + MU key — calculate percentages easily, including MU key percent calculations with a single press. Backspace correction — revise mistakes quickly without starting over. Compact handheld size — portable 4.6" x 2.8" design that fits neatly on desks and in bags. Battery included + auto-off — runs on one LR1130 button cell battery (included) and powers down after 8 minutes of inactivity. Pastel green style — a fresh, calming color that looks cute on any desk. Safety note — WARNING: CHOKING HAZARD - Small parts. Manufacturer recommended age: 3+ years . Not for children.