The Cinevate CIPCPC000006 Proteus Cage add on kit serves as a light, stiff and rock solid handle for your 35mm adapter, HD cam, or ENG cam rig. You can mount up to three universal rails blocks to the rig allowing the mounting of additional 15mm rails on either side, or on top of the rig.
There are mount points for an allen key holder and hot shoe mounts in case you need to mount mics, wireless transmitters, etc, to your rig. If that's not enough, the top bar is designed to accept sliding clamps to secure a small laptop up top. The unit is 100% computer machined from aluminum, computer bent and then powder coated black for a lifetime of use.