Using these Westinghouse cooktop control knobs is a breeze. Simply align the flat side of the shaft with the flat side of the cooktop's control mechanism and push the knob onto it. Make sure it fits snugly. When turning the knobs, do it gently to adjust the heat settings on your cooktop. As for maintenance, clean the knobs regularly with a mild soapy water solution and a soft cloth. Avoid using abrasive cleaners that could scratch the surface. If you're not sure if these knobs are suitable for your cooktop, always contact us with your model number and PNC code before making a purchase.