He was in SEG, which it what we call Solitary Confinement. It's a room with a steel door, not bars.  Some of them have a glass door instead of steel, from floor to ceiling, so they can be observed 24/7. Nothing in the cell at all except for a concrete slab for a bed, and a combo toilet/sink.  The ceiling is too high to reach, and anti-ligature hardware is installed to prevent, say, hanging yourself by the doorknob.