Radial Engineering SB-5W WALLDI Wall-Mounted Stereo Direct BoxRadial Engineering R800 0155 overview For AV installations that require sending unbalanced signals such as CD players or the output from a laptop to a live mixer or PA, the StageBug SB5W Wall Mounted Stereo Direct Box from Radial Engineering is made to fit inside a standard single gang electrical wall plate and provides stereo RCA and 3. 5mm stereo TRS inputs. It is fully shielded to eliminate any electrical interference and features a fully variable