Feature: 1. Fine quality plastics material case, with impact resistance and shockproof design, wear resistance and with fine durability. 2. Built-in integrated microchip with stable working performance, provides multiple protections and stable voltage circuit. 3. Built-in 5pcs 1300mAh battery cores, low heat radiation and quick heat dissipation, easy charging and with long endurance. 4. Temperature protecting, overtime protecting, overcharge protecting, overcurrent protecting, overpressure protecting, and with protective panels to protects the battery. 5. Purchase this replace battery can help you get work done more quickly, time saving with higher working efficient. Specification: This is a kind of fine quality 21V rechargeable lithium battery, can help you get work done more quickly, time saving with higher working efficient. Built-in 5pcs 1300mAh battery cores, low heat radiation and quick heat dissipation, easy charging and with long endurance. Features: Fine quality plastics material case, with impact resistance and shockproof design, wear resistance and with fine durability. Built-in integrated microchip with stable working performance, provides multiple protections and stable voltage circuit. Built-in 5pcs 1300mAh battery cores, low heat radiation and quick heat dissipation, easy charging and with long endurance. Temperature protecting, overtime protecting, overcharge protecting, overcurrent protecting, overpressure protecting, and with protective panels to protects the battery. Purchase this replace battery can help you get work done more quickly, time saving with higher working efficient. Specifications: Name: Replacement Battery Battery: 1 * 21V, 1300mAh battery (5pcs * 1300mAh lithium battery cores type) Package size: 130 * 110 * 50mm / 5.12 * 4.33 * 1.97in Package weight: 300g / 10.58ounce Packing List: 1 * Replacement Lithium Battery Package List: 1 * Replacement Lithium Battery