When we ran a full service chassis fab/turn-key hot rod shop a number of years ago, it was always useful to have threaded things around to weld into the frame for some kind of mount, etc.
Here’s a list of all our threaded things for your reference:
Gusset, 5-1/2" x 1-3/4"
Product Details
Brand: Welder Series
MPN: 214602
Country/Region of Manufacture: Canada
Thickness: 3/16"
Laser cut from pickled & oiled 3/16" mild steel. Great to keep around for gusseting crossmembers etc.