This set of five springs is great for in depth studying of the principles of Hooke's Law. Each spring has a different constant. For use with Eisco Labs Hooke's Law Apparatus (PH0322). The springs are as follows: Spring constant | Maximum weight 10g/cm |100 g 20g/cm | 225 g 50g/cm | 550 g 100g/cm | 1100 g 200g/cm | 2200 g