Due to its malleable iron construction, these Clamp Backs offer the heaviest-duty solution for providing space between mounted conduit and a variety of mounting surfaces. This Clamp Back is designed to be used with malleable or aluminum conduit straps. Malleable iron, due to its strength, rigidity and ductility (ability to flex without breaking) makes these straps highly resistant to damage caused by crushing or physical abrasion. Zinc plating offers even greater corrosion resistance over time. These Malleable Iron Clamp Backs are available in trade sizes 1/2†through 4â€. Bridgeport products are manufactured for innovation, consistency and quality — providing you with everything you need to do your best work at a lower total cost. And we build every product with the same goal in mind: guaranteeing a fast, professional-grade, trouble-free installation that meets or exceeds code requirements. When you need a solution you can depend on, be sure to look for Bridgeport Orange.