A silo feeder with a number of major advances The feeder has a guard which keeps debris, shells and hulls from falling outside of the cage -- the biggest problem consumers are consistently report with bird-keeping -The gravity fed feeder prevents "hull build-up" on top of the seeds as new seeds fall out of the silo onto the tray, they push the old hulls out. No need to carry a separate inventory- silo feeder for fits horizontal and vertical bar cages. Screws into the cage to guaranty a secure fit. Easy to clean- Dishwasher safe or use with JW Cleaning...