having problems finding a...

adapter ring/bellows like/stretch doughnut thing (there are so many names i dunno) for the MB-600 Mattebox. anything to stop light reflecting from my nd filter on the lens when it isnt fully extended.\
Anybody have any knowledge of this?

Yes I know..."Newbie question" "do your research" I am not one to like asking for help at all let alone such a generic inquiry to such a specific issue...But on B&H website all of the 'universal' rings with a 50 to 85 cloth shade cover state very specific thread sizes for the matte box itself...never one of them for the matte box I have.

Make one.

Grab a sheet of neoprene (wetsuit material) cut a circle. Diameter about the height of the matte box.

Then cut out a circle in the middle that is smaller that the front of your lens. About 60cm is normally ok.

Stretch it over the lens and it will press up against the back of the matte box.

Sorted.

I first saw this a few years back on the set of a commercial. The 1st AC pulled them out of her bag and I asked where she got them. Then she explained.

Kamerar sells one. I like my Kamerar Matte Box so far.

http://www.kamerar.com/products/mattebox-donut