Resideo's Piezo Dynamic (PD) 747PD Siren produce traditional speaker sound while drawing 1/4 the current of typical sirens. This allows multiple devices to be installed on the same alarm panel without the need for additional hardware, costs and labor. The sirens feature a sleek, lightweight design, an easy-to-wire terminal block and a hinged case cover. The 747PD Siren are globally compliant and UL approved and ideal for residential application.