Abstract: A spring for compression and tension mainly in an axial direction and made of a material having a Young's modulus of elasticity of at least 39 GPa, such as metal, steel, glass, plastic or reinforced plastic is disclosed. The spring is in the form of a tube or ring of generally constant thickness. In cross-section, each ring is made up of oppositely directed inner and outer U-shaped spring parts with contiguous axial projections. A spring is provided which has minimal elastic hysteresis.