A 4 oz. bag of Simple-Plastic. Melt pellets to between 138 and 160 degrees Fahrenheit and watch them become clear and start to fuse together. Plastic becomes workable for approximately five minutes, then hardens and becomes strong within fifteen minutes! Can be cured faster by placing in cold water. Remelt and reuse over and over! Great for mechanical prototypes/parts, arts/crafts/RC hobbies, industrial applications, and home repair!