The sack makes the noise of a paper bag that all kitties love. The inside is lined with plush lambs wool Sherpa. The outside is covered in poly/cotton for easy washing. Cats will play and be amused for hours and this will become one of the favorite hiding places. Makes noise of a paper bag that kitties love Inside lined with plush lambs wool Sherpa Overstuffed bolster keeps sack open for easy access Easy wash and care Sleeping Dimensions: 15 x 18