The square Form Ten H Style arm mounted luminaires are attached to the poles with an extruded aluminum arm which effects a subtle distancing of the luminaire from the pole, without the use of any exposed hardware. Simplicity of design assures good looks in single, twin, three and four-way configurations. All Gardco housings are permanently sealed and gasketed to be rain-tight, dust-resistant, and insect-proof. The H style features one piece, multiformed aluminum with an integral reinforcing spline and a single concealed joint. Tops are press formed with a returned perimeter flange which is internally welded with the housing sides.