BP18LI 4.0Ah HPC-ASI BATTERYLi-HighPower Compact Battery: fatigue-free operation thanks to a weight of less than 600 grams. This makes it 20% lighter and 50% more compact than a standard 5.2 Ah battery. This only means lower weight, but not power. Thanks to Li-HighPower cell technology, it has enough power for any application. Of course, it is also covered by Festool Service's comprehensive protection.Fatigue-free work: weighing less than 600 g, the battery is 20% lighter and 50% more compact than a standard 5.2 Ah batteryFull power: thanks to Li-HighPower cell technology, it has enough power for every applicationExtraordinary durability is ensured by cells that can withstand high currentsWork without worry every day: Of course, the batteries are also comprehensively protected by Festool ServiceDischarge starts automatically: The Bluetooth variant automatically starts the connected mobile vacuum cleaner when the tool is switched onLithium-ion (Li-Ion) Bluetooth batteries with AIRSTREAM function for all Festool 18-volt cordless tools (except CXS, TXS, ETSC 125, RTSC 400, DTSC 400)Bluetooth allows the CLEANTEC mobile vacuum cleaner to start automatically when the cordless tool is turned on (provided the mobile vacuum cleaner supports Bluetooth)Perceptibly lighter while maintaining full powerAbsolute reliabilityTechnical dataVoltage 18 VCapacity 4.00 AhWeight 0.60 kg.