Fushield 18V 4.0Ah Replacement Bosch BAT609 Power Tool Lithium Ion Battery for Bosch BAT609 609G 618 618G 619 619G --12 Months Warranty Advanced Production Technology: Advanced automatic resistance instrument detects the resistance and voltage; Quality Guarantee: Each battery need to be charged with original tool, qualified by the instrument and circulatory testing; High-quality after service:Professional engineers group is on call with 12 months warranty.