The tension helical spring has hooks at its ends, in addition to the coils. The hooks are also called eyes.

For the tension helical spring to perform its function, it must be stretched, increasing its length. At rest, it returns to its normal length.

The helical spring is the most commonly used in mechanics. It is generally made from steel wound into a cylindrical or conical helix. Helical springs can operate under compression, tension, or torsion.