For sale is a used KLH (Burwen Research) Dynamic noise filter. The model number is 1201A. Rack mount. There are several small scratches on the unit as shown in photos. You will receive everything as shown with your purchase. If you have any questions, please feel free to contact me. Mark 

BEFORE LEAVING FEEDBACK PLEASE CONTACT ME. I WANT TO MAKE YOU HAPPY AND FIX THE ISSUE.