The Knobby Balls come in a pack of 12, and each ball has a size of 3 inches. These balls are also known as sensory balls due to their unique features. They are covered in squishy spikes all around, providing a tactile and sensory experience when touched or squeezed. The balls come in assorted colors, adding visual appeal to their design. They are sold inflated, ready to be used right away. Its important to note that these Knobby Balls contain latex, so individuals with latex allergies should exercise caution when handling them.