Our standard F-series masonry frame is the best stock hollow metal assembly in the industry. We use only the best materials, such as 16 or 14 gauge cold rolled steel or A60 Galvannealed steel for corrosive applications. To insure consistent and accurate quality, we also use state-of-the-art technology, such as our computer-controlled MIG welders and an overhead trolley line paint booth. We surpass the industry requirements by using 3/16 inch hinge reinforcements to outlast the heaviest hollow metal doors.