Vocas 0420-0001 (04200001, 0420/0001, 0420 0001, 0001) 144 mm Flexible Donut Adapter Ring for MB-450.
The Vocas Flexible Adaptor Ring Kit (144 mm), which includes an adaptor ring and holder for an additional 138 mm round filter, is compatible with the MB-450 mattebox. It also includes exchangeable flexible soft rubber rings (donuts). The adaptor ring prevents light from leaking between the lens and the rear end of the MB-450 (when used on a rail support).
Using a quick lock system, the adaptor ring securely attaches lenses with a front outside diameter of 80 to 138 mm to the mattebox. When used in combination with the holder for the additional 138 mm round filter, the adaptor ring allows for a maximum lens diameter of 133 mm.
In The Box