Paillard Bolex Lens Hood & Filter Holder For Som Berthiot Zoom Lens On P1 P2 P3 8mm Movie Camera
The filter holder accepts all 50mm diameter Series VII filters (see other items for filters to fit this).
The lens hood screws onto the filter holder (with or without a filter inserted) and then attaches to the lens (see last photo).
Good condition with very minor marks from use.