Opened but unused. Please check the photos for the condition. Feel free to comment if you have any questions. Thank you. [Product Description] AIRCRAFT-specific lithium-ion battery. Can be used at maximum output (24V). ● High-spec battery that delivers an average airflow of 105 liters per hour ● Approximately 4 hours of rapid charging Product Name: Lithium-ion Battery Product Number: AC09 Manufacturer: Bartle Color: Matte Black, Metallic Gold, Metallic Red Materials: Lithium-ion battery body x 1, rapid charger x 1, instruction manual/warranty x 1 Compatible Models: AC09-1, AC09-2 (2025 model), AC08-1, AC08-2 (2024 model), AC370 (2023 model), AC371 (2023 model), AC310 (2022 model), AC311 (2022 model) Specifications: Battery Capacity / 4,900mAh/14.52V (71.5Wh) External Dimensions: H113mm x W83mm x D29.5mm Charging Time: Approximately 4 hours Operating Time *1 / 24V: 1 hour + approximately 5 hours (average 68 liters/second) *2 18V: 2 hours + approximately 6 hours (average 68 liters/second) *3 10V: Approximately 11 hours 7V: Approximately 30 hours *1 This is the value when fully charged. Operating time varies depending on wearing conditions and environment. Differences in continuous operating time are not covered by initial defects. *2 24V voltage (airflow) automatically switches to 18V after 1 hour of use and operates at an average of 68 liters/second. *3 18V voltage (airflow) automatically adjusts the airflow after 2 hours of use and operates at an average of 68 liters/second. Engineered by KYOCERA Industrial Tools