After a simple assembly, your DNA Model will be ready to spring from a double helix and separate down the middle. This beautiful permanent model coils and uncoils with a touch of the hand. It is ideal for showing base pairs and the near infinite combinations possible. Whether you are teaching biology, chemistry, forensics or physics; this is a beautiful addition to your science classroom. Appropriate for elementary school, middle school, high school, and college! Approximately 34 x 5 inches fully extended. Collapses to 9 inches high.