FROM AN AMERICAN COMPANY: A 4-pack of the most popular type of plastic bee feeder for beekeepers; it makes it easy for the beekeeper to feed bees with water or sugar syrup, an essential part of your supplies. ^ CLASSIC DESIGN WITH MULTI-STAGE ENTRY: Also known as a boardman entrance feeder or front feeder, it can be used at the entrance of most beekeeping equipment manufacturers or inside the hive as a top feeder; each plastic feeder base and lid measures 5.5 inches long, 3.25 inches wide, and 7/8 inches high^ FITS MOST JARS: Hive feeders work by screwing a filled, standard small-mouth canning jar onto the included lid and inverting the tray because the vacuum pressure in the jar prevents the syrup from dripping out of the holes. Not all jars are made the same so test the lid with several jars to get a tight seal.^ THE STANDARD FOR BEEKEEPERS: Very easy to use and beginner-friendly as you can easily monitor syrup levels from outside the hive; the optional and removable snap-on bottom makes cleaning and removing the jar lid easier ^