Specially designed for cordless sanders: The Ergo battery pack is developed for the ETSC 125, RTSC 400, and DTSC 400 cordless sanders. Continuous operation is possible thanks to the battery packs with a capacity of 3.0 Ah, which offer longer run times than charge times. Unique - with battery or cable: For all applications that require even longer run times, the 18 V Ergo battery pack can be replaced with the plug it mains adapter (included in the set and available as an accessory). When combined with the plug it cable, it creates a mains machine with unlimited runtime - ideal in combination with a Festool mobile dust extractor. Practical: An LED display quickly shows the remaining capacity. Comfortable: Bluetooth enables the automatic starting of the CLEANTEC mobile dust extractor when the cordless tool is turned on (assuming a Bluetooth-capable dust extractor is used). Smartly enhanced: The Festool WorkApp, in combination with the Bluetooth function of the battery pack, offers clever additional features, such as detailed display of the charge level and other operating data like temperature or charge cycles. To quickly and easily identify the battery with the lowest charge, the LED display on the battery pack can blink. Software updates are also possible: Install the latest version to always work with the newest features of the tools. For worry-free everyday use: Naturally, the battery packs are fully covered by the Festool Service. Specifically developed for the ETSC, DTSC, RTSC cordless sanders: The lightweight, handy Ergo battery pack ensures full freedom of movement and maximum comfort while sanding. The perfect interplay between the battery pack and EC-TEC motor provides endurance like that from a socket, achieving longer run times than charge times. Equipped with Bluetooth, it automatically starts a paired dust extractor when the cordless tool is turned on.