Multi Color Ceramic Fiber River Rock - 84 Piece Assortment Adding a natural touch your fire ring or pit is easy with the Hearth Products Controls River Rock Kit. This kit contains an assortment of over 84 large (4.5 ) and small (2.5 ) stones and is perfect for indoor as well as outdoor use. It is built to withstand exposure to the elements and the gel-cast ceramic fiber design makes it lightweight and portable. The combination of brown, gray, and black colored stones is sure to improve any home or outdoor scene. Fire Pit Media Especially Designed For Use With Fire Pit Burners And Rings. Lightweight gel-cast ceramic fiber construction. Easily withstands exposure to the elements. Attractive combination of brown, gray, and black colors. Can be used indoors or outdoors. Includes an 84-piece assortment of large (4.5 ) and small (2.5 ) stones.