Using this Asko switch is easy. Just press the button on the switch with the white knob, and it will perform its momentary function. When installing it, make sure to connect the 4 spade terminals properly to the relevant parts of your Asko front - loading washing machine or dryer. As for the models it fits, if you're not sure, you can check your appliance's manual or contact Asko. Since the switch is no longer available from the manufacturer, handle it with care. Avoid using excessive force when pressing the button to prevent damage. For maintenance, keep it clean and dry. If you notice any signs of wear or malfunction, it's advisable to replace it as soon as possible to ensure the proper operation of your appliance.