These are designed to be used with the Blichmann BoilerMaker Brew Kettles for use in a mash tun. Will also work great if you're using whole hops in your boil kettle (for pellet hops, we recommend using the Blichmann HopBlocker). A patent pending button louver design is a hybrid of a perforated false bottom and a slotted manifold to give you the best of BOTH designs! 7.5 gallon, 10 gallon, 20 gallon, 30 gallon, and 55 gallon false bottoms are G1 and G2 compatible. 15 gallon is G1 OR G2 compatible.