Bc4z-r, 4x4 post cap/base z-max, reduces the chance of the post splitting & eliminates nailing into end grain, provides an easy & secure connection between post & beam, made with 18 gauge galvanized steel, install with three 16d hdg commons or 16d x 2-1/2" hdg joist nails into each side on surface a, three 16d hdg commons or 16d x 2-1/2" hdg joist nails into each side on surface b, total 12 16d hdg commons or 16d x 2-1/2" hdg joist nails.