K&F Filter System - Alternative Filters

[flook999]

I have a K&F Concept square filter system, and am looking for a 2 or 3 stop soft ND grad, but can't find one in the UK. Anyone know if other suppliers filters work with this system? The system takes 100mm filters at 2mm thick, so I'm thinking Lee filters 100mm system, but I can't find any information on how thick they are

edit, found it, 2mm thick. Still open for alternative suggestions though

 

[old_codger]

I've got 100mm square and 100x150mm filters from a bunch of manufacturers, and they all seem to fit my Nisi holder without a problem. When I needed a 3 stop soft grad recently I went cheap and got one from Jack The Hat Photographic, branded pixel peepers. It works fine, no notable colour cast. I've no idea how accurate the 3 stops claim is though.

 

[Dangerous]

You could look at the Lee Filter but sit down before looking at their price.