Springs
![](/Content/images/customize/PSpring-individuals-open 450_w.png)
Spring hinges usually use wound torsion springs like these. They can be made from steel or stainless steel, and can be plated.
![](/Content/images/customize/PSpring-individuals-close 450_w.png)
The springs for opening and closing differ mainly in the legs. The bend in the closing spring legs allows them to poke through to the back side of the hinge to press the leaves closed.