The Grumpy Cat Catnip Sock is made of a thick hessian material, filled with crinkle sounds and catnip. It's an excellent quality toy for cats to bat around on the floor and activate its jingling tail! Grumpy Cat became an internet sensation in 2012 after her owners posted a picture online of her grumpy face. She has since become an internet celebrity all over the world. Our Grumpy Cat range are official licensed products made from only the best quality materials and textures, including catnip filled cat toys and a floppy plush cat dog toy.