UMB-1 Universal Mattebox (Base) comes standard with two rotating 4x5.65 filter stages (with an optional third stage available), individual tray catchers, folding French flag, 143mm diameter opening, a height adjustable 15mm LW rod bracket which can be adapted to studio rods a universal cloth donut with easy to grab finger loops, and NATO standard accessory rails on left, right, and top for attaching accessories. The UMB-1 is designed to be user upgradable and quick to transition from base, to clamp on, to swing away, to ultralight when using a stabilizer. Upgradable to Swing Away or Clamp On versions when needed.