Portability and ease of use makes it perfect for workshops, travel and daily use."Original Felting Stone" approximately 3.25" x 2.25". Each Stone is hand painted and unique. Felting stones are used during the fulling process in traditional felting. The corrugated surface is used just like a washboard. Their small size enables you to have greater control when felting hard to reach areas. In addition they are extremely portable. Each is made by hand from natural earth clay, bisque fired, glazed and fired again.