Just bought this one today. The Wix part number is 51061, this Napa one is 1061. Obviously same part, made at the same place.
I know others had said Wix was now made in China, but this one still says USA.
I used to buy them from Napa but their cheaper at Apex Auto in Oshawa. Not sure if Apex exists anywhere else. I buy them by the 12 pack. Made in USA.
I can buy a set of AC Delco plugs cheaper at Apex than with my discount at GM.