Nady Fs-4n Feedback Suppressor: * 4 narrow notch filters * Inline 8-band spectrum analyzer * 1/4" TRS balanced jacks for both signal in and out * Internal shielded power supply with external fuse and AC select switch * Single rack space * Rugged metal house for reliability * IEC power cord socket for AC operation and screw terminals for optional +24 VDC input powering