GENUINE FENDER KNOB + CAP BLACK FENDER S-1 SWITCH STRATOCASTER. You will receive ONE black push-on knob for use with S-1™ switch.  It can be retrofitted to nearly any U.S.- and Mexico-made Stratocaster  manufactured from 1954-present. Fits 1/4" split shaft controls. Part Numbers: 0059267029 Free Shipping