These vine balls (2-1/4") are hollowed - perfect for a foraging toy. You can put dry hot chili peppers, almonds, dry fruit, Nutri-berries, Peanuts or any other treat you can think of inside these vine balls - BE CREATIVE! Your bird will have a blast getting the treats out and destroying the vine ball. We have not yet met a bird that didn't LOVE destroying these toys! These balls, made from rattan vines and shaped like eggs, have been put through a bleaching process to give them their lovely color. They are completely safe for all birds, and are free from insecticides, paint, oil, or any toxic substances.