Set of 6 durable steel springs with looped ends Compressed spring dimensions are: 6.25" x .5", 8" x .6", 6.5" x .75", 7.5" x .6", 8.25 x 1", 9" x .4" Ideal for depicting Hooke's Law and other physics concepts Designed for classroom use Flexible length between 10-20cm The Eisco set of 6 steel springs is ideal for classroom demonstrations involving Hooke's law and other physics concepts. Each spring is made of durable steel, and the variety in size offers a range of responses for students to examine.