The Lee b/w polyester set, including the gel snap holder, is only $65.
I've used this durable set from the beginning, with great results.
You would, of course, need the Lee regular holder (2nd image) for the 4"x6" GND filter. This regular holder (which snaps onto an adapter ring, and rotates around it) will also hold the 4"x4" b/w polyester filters.
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