This is a new contractor for me, found on the west side of South Fairview Avenue between Elizabeth and Harton, in the Urbandale neighborhood. I can’t seem to find out anything about H. Widman the contractor. There was a Harry Widman who was active in the Capitol Grange in the 1940s and 50s, but I don’t know if there is any relation.
The stamp is in front of a house with a walk-out basement, which is very unusual for the neighborhood. I don’t think I’ve seen another like it around here.