System accessory GCT 30-42 When you are working with a vacuum cleaner, you usually have to operate the vacuum cleaner as well as your tool. That's why Auto-Start was developed to synchronise cordless tools and vacuums wirelessly so that they start and stop automatically at the same time. The GCT 30-42 Professional auto-start module can be easily attached to many cordless tools using the three rubber bands supplied. Quickly pair the GCT 30-42 Professional with an external auto-start plug or a connected vacuum cleaner at the touch of a button. And you're ready to go. The auto-start module recognises vibrations from the running tool and automatically switches the vacuum cleaner on and off for you. So you can concentrate fully on your work. Auto-Start operates your vacuum cleaner while you concentrate fully on drilling, chiselling, cutting or sanding. You can use Auto-Start wherever you need a cordless tool in combination with a vacuum cleaner. 3 x flexible rubber band. 1 x 3 V CR2032 lithium button cell battery.