Came out great. printed with 30% Honeycomb infill, holes are ~2mm or smaller which works perfect for my carbon from activatedcarbondepot.com It's a bit snug and makes it harder to remove, but I added some 3/8" wide x 3/16" thick weatherseal around the perimeter to make it air tight so any vented air HAS to pass through the carbon. if you do this, the filter cover does still fit, but you need to firmly press around the entire perimeter of the cover to get it to fully latch/not bulge out.