Small Portable Sand Tray with Lid - Pink No mess up Sand Box! Store or carry it wherever you want with Small size, Stackable, Waterproof, Durable box with locking LID. Sand not included. The size of the tray is meant to hold a person's steady gaze which may encourage a concentration and build up the frame of mind. Let the imagination begin with Sand play. The Sand play therapy could be fun. Your kids can connect with active imagination, feelings and experience and ultimately their inner self. The variety of figures, the touch of sand and water stimulates physical, cognitive and social skills. Sand play encourages freedom of ideas. Your child is free to use innovation and build their your own three dimensional sand castle or scenes with small toys. Encourage your child for problem solving, perspective taking, and/or consideration of feelings.