US Patent 9148007 Recessed poke-through fitting

A poke-through device includes a tubular main body sized for insertion into a hole formed through a concrete floor. A device frame is mounted in the tubular main body for mounting one or more electrical devices. An intumescent insert is mounted in the tubular main body below the device frame. A junction box assembly is mounted to a bottom end of the tubular main body. A cover assembly is configured to enclose an opening in a top end of the tubular main body. The intumescent insert is mounted in the tubular main body so as to not contact the device frame to allow intumescent material to flow around the device frame in the event of a fire.