The Camtree MB-23 wide angle carbon fiber matte box is a solid but lightweight matte box system that will help you protect your lenses from extraneous light. It is easy to use and has a swing away feature that will make it easier for you to change lenses fast without having to take the matte box off the rails. This Camtree matte box comes with PROAIM RS-1 rail system and the PROAIM X1 follow focus. For an additional $10 you can include a high quality 4x4 Tiffen ND filter, either the 4x4" Neutral Density 0.3 filter, the 0.6 or 0.9. This swing away matte box also comes with foldable french flags, a fabric cover that completely eliminates light and wraps around your lens (knicker) and 2 4x4 filter holders.