Yarn balls are one of the very first cat toys to ever be "made." We say this lightly because it wasn't until a cat began playing with a ball of yarn being used in a knitting project that anyone ever thought to make it into a toy.  Unlike the human ball of yarn, these toys are made smaller and are more durable....no long strands of yarn to get tangled up in or swallowed.  The yarn is knotted in the center and the ends trimmed to 1.5", the perfect size for kitty to bat around the house.  Hours of fun await your wild feline!