These “A stands” are made from 3/8″ AR500 steel. They are the most versatile stands on the market! They use easy to come by 3/4” emt conduit or equivalent for the legs. You can use a 2×4 for the cross member or anything from 1/2″ – 1″ in diameter in one of the 4 corresponding holes. The hooks where specifically designed to fit perfectly over a 2×4 and still work with a round cross member.