This simple-to-install MantelMount add-on accessory allows you to integrate seamlessly into a custom-built wall opening. Easily fitting between standard or custom stud configurations, The RB100 Recess Box provides a super flush TV-to-wall storage by allowing the MantelMount center arm to fold into the wall when the TV is in the raised position. The result is concealed mounting hardware and a 1.8 inch flush-to-wall TV storage!(For Mount Models MM340, MM540 and MM700 ONLY).