it is a ball and socket. Here is a picture of mine. I can go take one from a different angle if you want.
http://i1152.photobucket.com/albums/p494/69B-Cuda/wiper%20pivots_01.jpg


Mike
1955 Chevy 6400 ex-flatbed (no bed now!) sold September 2023
In the Stovebolt Gallery
1958 Chevy 6400 flatbed W/dump
In the Stovebolt Gallery
1959 Chevy Suburban Owned for almost 20 years, Daily Driver -- sold May 2016
In the Stovebolt Gallery

Sufficient unto the day is the evil thereof