The James Knights Co. FS-344 Frequency Standard Tube Amplifier Unit is a vintage audio and video device that operates on the principles of vacuum tube amplification. Featuring the brand’s signature quality and reliability, this model is designed to provide a consistent and stable frequency standard for audio and video signals. Perfect for collectors or vintage electronics enthusiasts looking to enhance their home audio setup with a touch of nostalgia and craftsmanship. USED. NOT TESTED. THE POWER CABLE HAS A BREAK IN IT. THE TESTER CABLE NEEDS REPLACED BECAUSE OF BROKEN WIRE. PLEASE LOOK AT THE PICTURES FOR ANY IMPERFECTIONS. THANK YOU.