The size of the balls is great, my cats can hold them between their paws, and the soft material is perfect for clawing into. They would be even better if they were made of wool instead of synthetic fibre.
This set of three balls is a real hit with my cat. She loves rolling them around, chasing them, and playing with them for ages. The balls make a soft noise when they roll, which sparks her curiosity and playful instincts, but it’s quiet enough not to be annoying day-to-day.