What is the difference?
Tension springs or a tension spring is basically the same as an extension spring or springs. It doesn’t matter if they are large extension springs or small extension springs as has been implied, a tension spring supplier or tension spring manufacturer is just as equipped for extension spring design and extension spring testing as they are for tension springs. With so many terms for the same thing, it can be confusing.
Take another example. A helical coil spring or helical compression springs, whether they are small compression springs or large compression springs, are compression springs that can be manufactured by spring manufacturers who are large compression spring suppliers, small compression spring suppliers, stainless steel compression spring suppliers, and steel compression spring suppliers. Size and material type do not differentiate spring types.