The PD-60AT is a fully environment-resistant 60 watt driver for indoor or outdoor applications recommended for use in expansive and/or high ambient sound-level areas. Unit features a sound chamber, phasing plug and magnetic-structure components machined to optimum tolerances. Plane wave frequency response is 100 - 3,700 Hz (+5dB). The PD-60AT features a built-in varnish impregnated, multi-tap 70 volt line-matching transformer. Corrosion-resistant terminal connections are protected by a transparent, impact-resistant plastic cover which provides strain relief for the interconnecting cable. The PD-60AT is terminated in standard 1 3/8"-"18" thread male couplings for use with screw-on horns.