|This 3 5/8-inch tumbler is named for the horseshoe molded into the bottom. There is also a version without the horseshoe, referred to as unshod. This one sold at Bob Smith's tumbler auction in 2019 for $5; an unshod example went for $2.50.
Bob elsewhere pointed out that he had discovered that at least seven companies made such a pattern.
Photo courtesy of Wroda Auctions