The SmallHD Mounting Cage for 503 UltraBright Monitor includes two metal brackets that attach to the monitor and provide mounting points for accessories. The brackets mount on the left and right sides of the monitor and provide 1/4"-20 and 3/8"-16 threads for accessories. They also feature slots for attaching the optional dedicated sun hood for this monitor, which secures by magnetic mini-rods into these slots. Four screws are included for attaching the cage to the monitor.