This 48" single post square picnic table has a center post that is made of 6 inch square tube which makes this unit extra heavy-duty. The seat arms are 3 1/2" O.D. pipe. The entire frame is hot-dip galvanized after fabrication for long life. In-ground is standard on single post tables. This picnic table features a vandal resistant design with the post being approximately 20" into a concrete poured base.