The Knob is an OEM component specifically designed for Whirlpool electric dryers. Located on the control panel, the knob allows for the selection of desired drying time, temperature, or fabric care settings. Its sturdy construction assists millions of adjustments over the appliance's lifespan. Causes of a bad knob can include normal wear from continuous rotation breaking down grease on internal mechanisms. Over-tightening during installation may crack the plastic. Symptoms of a bad knob include: Difficulty selecting options or inability to turn    Knob slipping out of set position during drying   Loose, shifty, or jittery feeling during adjustment Cracked or broken casing tabs exposing internal parts This OEM Whirlpool part is also compatible with KitchenAid, Maytag, Amana, Roper, Admiral, and some Kenmore dryers.Part Number W11676494 (AP7215412) replaces W10215799.