A golf-ball-sized wiffle ball. Measures a little over 1.5" with slightly less than 1/4" holes. These are sturdier than the ones we have carried in the past. We thought small ball = small bird, right? Wrong. Turns out that birds of larger sizes love the small balls because they are easy to grasp in their feet. The holes are also perfect for Polly Rope, All Sizes of Hemp, Plastic Lacing or all sizes of Round Leather Laces if using as a Toy Part.