LED quantity: 18 pieces Luminous flux: 6lm/LED Input power: USB 5V/500mA Lithium battery capacity: 3.7V/100mAh Power for calendar: CR2025/3V (included) Materials: ABS and PS Calendar display (time, day and date) Alarm with snooze function Temperature display Eco-friendly, available 2-grade brightness Built-in rechargeable battery Fantastic design and long lifespan