The Omni tray can be attached to the bottom of the Droll Yankees feeder with a pastic threaded plug (furnished) or a wing nut (not furnished). It is a simple task to complete and no tools are needed. The tray has a a number of holes around the outer perimeter of the feeder to let water drain. Having a tray means not only preventing seed from falling to the ground but also attracting birds that are too big to use the perches. The few seeds that do fall on the ground are soon consumed by doves, if they can get to them before the squirrels arrive.