A 1/4" diameter, 18" long brass stem with a pointed top end, fitted with a 2" x 3" brass plate. Carve the 4" x 8" x 8" Ethafoam block to fit inside your hat, stick it on the pointy end of the brass stem. (To finish off, we cover the top part of the Ethafoam with stockinette and cut a sheet of dark felt to cover the bottom of the Ethafoam, including the brass plate. The stockinette is kind to the object and the dark felt helps the mount "disappear".) Then bend the stem to the shape you need. Install in deck or wall.