These are perfect for use with either a cyclone, or Phil Thien separator (ask Bas.). Currently listed in "Farm and Garden" section of RDU Craigs list. The plastic lid is easier to make a hole in. You use a piece of wood with two nails in it. One is the pivot, and the other is the cutter. Make several passes, and produce a perfect hole. Buy two so you can keep going while the other is waiting to be emptied. Bruce