With the ECOVACS WINBOT W3 Family microfiber cloth with holder, you can replace the mopping pad of your window cleaner. You can easily replace your old, worn-out, or dirty chamois with the new microfiber cloth with holder. This way, your robot cleans your windows thoroughly again. You'll always have a clean cloth on hand when the dirty one is in the wash. With the included holder, you can easily click the microfiber cloth onto the robot. You should replace the chamois after 90 days. With this pack, you get enough mopping pads for 180 days. You can only use the microfiber cloth with holder on the ECOVACS WINBOT W3.