This is a NOS Ford AC blower speed switch which is correct for all 1966 Mustangs equipped with factory AC. It is correct original NOS Ford and will fit and function flawlessly. These parts are very hard to find and not reproduced. Some vendors are selling a cleaned used switch, whatever that might be, good luck with that one! This one is old school NOS Ford. No import repro crap here, all original NOS Ford.