Brand new, unused. BURTLE 24V battery. Burtle AC09 Aircraft Lithium-ion Battery. 2025 latest model AIRCRAFT dedicated lithium-ion battery. Can be used at maximum output (24V). Product Name: Lithium-ion Battery Product Number: AC09 Manufacturer: Burtle Included: Battery body, rapid charger 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) 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 13V: Approximately 11 hours 7V: Approximately 30 hours *1 This is the value when fully charged. Operating time varies depending on wearing conditions and environment. *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.