Thickened corrugation; Thicken the suction cups so that they can stay stationary even if there are many birds feeding at the same time in the suction cup bird feeder window. Rugged.
Replacement of suction cups at the bird feeder window; Bird Window Feeder Suction Cup, this suction cup replacement is easy to install and remove, and can adhere to any smooth surface
HOw to use; Clean the surface with rubbing alcohol before use, soak in warm water for a few minutes, and then moisten for better results.T
