Abstract: Helical tension spring having a spring body and two eyelets or loops integrally formed with the body of the spring at the ends thereof, the free ends of the eyelets contacting the end coils of the spring body. Each eyelet is under a prestress force which has to be overcome in order to lift the eyelet from the adjacent end coil of the spring body, such pre-stress force being larger than the force applied at the eyelet, which force is necessary to separate the coils of the spring body by a certain distance.The invention also relates to a process of producing the above spring. At both of the end coils of the spring body there is formed a wire section in a plane approximately normal to the spring body.