Amazon.com : AUXPhome Bird Seed Catcher Tray Platform Feeder Hanging Tray Outdoors Backyard Garden for Bird Feeders, Great for Attracting Birds Outdoors, Backyard, Garden. Help Reduce Seed Waste - No Feeders :
BIRDS CHOICE Rec. WM100 Tray, Cover and Cage Black Recycled Poly-lumber Window-mount (suction Cup) Platform Bird Feeder in the Bird Feeders department at Lowes.com
Twigs Platform Bird Feeder | Gardener's Supply
How to Build a Fly-Through Hanging Platform Bird Feeder (With Roof) - FeltMagnet