I was done waiting on my grinder to collect kief for smoking so I got out my bubble bags and used the 75 micron for sifting, I was happy with the product but it wasn't the easiest thing to do, trying to hold the bag open, move the buds around and keep it over the tray. I have been looking at a "trim tray" at the grow shop and decided to get one for $45 bucks off Amazon. It's awesome:thumbsup:for breaking up buds and collecting a surprising amount of kief. In about a week I get to try trimming my last harvest with it. I'm totally happy with tray so far. http://www.amazon.com/Heavy-Harvest-Trim-Tray/dp/B00HQ4XBEU