Features: 1) Lithium ion 18650 cylindrical rechargeable battery 2) 3.7V 2,000mAh high capacity 3) Higher energy density and lower weight than other types of rechargeable batteries 4) Manufactured under ISO9001 to assure quality 5) Internal PCB protects against under and over charging - low voltage 2.8V, high voltage 4.2V 6) Battery tested based on International Electrotechnical Commission (IEC) standard to ensure capacity, quality and life time Applications: 1) Built-in laptop batteries 2) Built-in portable power devices needing high energy density and low weight Cautions: 1) Use special caution when working with Li-ion cells, they are very sensitive to charging characteristics and may explode if mishandled 2) Make sure user has enough knowledge on Li-ion rechargeable batteries in charging, discharging and assembly before use 3) We are not responsible for any damage caused by misuse or mishandling of these Li-ion batteries Specifications: 1) Capacity: a) Nominal: 2,000mAh b) Min.: 1,950mAh 2) Dimensions: a) Diameter: 18+/-0.2mm b) Height: 68+/-0.2mm 3) Weight (typical): approx. 46g 4) Nominal voltage: average 3.7V 5) Cut-off voltage: 3.0V 6) Internal impedance: less or equal to 180 milliohm (with PTC) 7) Cycle performance: 90% of initial capacity at 400 cycles 8) Cycle life: > 500 cycles 9) Charge: current = 0.5C mA, voltage = 4.2V, end current = 0.01mA 10) Discharge: current = 0.5C mA, end voltage = 3.0V 11) Max. charging current: 1.5C mA 12) Max. discharging current 1.5C mA (for continuous discharge)