Unlimited running time: For continuous electrical operation, the 18 V battery pack can be replaced with the plug it n mains adapter, which is an ideal solution in combination with a Festool mobile dust extractor. Unique: With battery or cable. For all applications which require an even longer operating performance, the 18 V battery pack can be replaced with the plug it-mains adapter (included in the set and available as an accessory). This creates a mains-powered machine with an unlimited running time in combination with the plug it-cable – ideal in conjunction with a Festool mobile dust extractor. not compatible with all other Festool cordless tools. for continuous electrical operation of the ETSC 125, RTSC 400, DTSC 400 cordless sanders. ergonomic, lightweight design. for ETSC 125, RTSC 400, DTSC 400 cordless sanders