These are genuine Fender pickup covers. They'll fit most vintage-construction replacement Strat pickups perfectly.
Installation is simple; they slip on and off of the pickups with no tools. They also match Fender's knobs perfectly. Please note that not all covers and knobs look the same, even if you go with a basic color like black or white. Colors vary somewhat, as do the finishes on the plastic. So if you want matching knobs and covers, then you should buy all of the parts from a single manufacturer. Fender has these made here in the USA by a vendor who sells exclusively to Fender. So if you want the real thing in the right colors, you need to buy Fender parts.