Recently I was in a new customers condo and noticed that in the corner where the wall meets the ceiling there was some sort of a box that I have never seen before. This customer has someone else living in a condo above him so adding any hidden circuits in this type of condo has always involved doing wall and/or ceiling damage or installing surface raceway. After closer examination, it appeares to have been installed to cover the cut that results when trying to make the 90 degree turn with a wire when there is no access above the ceiling. Someone ran a wire up the inside of the wall from a wall receptacle and above the ceiling to the center of the ceiling for a fan outlet. Does anyone know what this box or cover is called and who makes it? Have I been living under a rock for the last 35 years?