The DH series fire door holders are constructed of the finest materials and workmanship available. The doorholder is made of durable die-cast metal and offered in a high luster powdercoat finish. Other features include standard dual voltage ac or dc inputs of 12 & 24V, 24 & 120V and 24 & 220V models. While reducing stocking requirements, model 24120 draws a mere .020ma. @ 24VDC lowering overall job costs. In large installations, the DH series door holder can account for substantial amounts of savings.