Abstract: A steel cord comprising a number (between 3 and 27) of element steel wires tightly twisted at a regular pitch P between 5 and 20 mm in the same direction. Each wire has a diameter d between 0.1 and 0.4 mm. At least one of the wires includes a spiral portion having a spiral pitch P1 between 0.1P and 0.7P and a spiral diameter d1 between d+2/100 mm and d+2/10 mm. At least one other wire includes a straight portion. At any cross section of the cord, 1/4 through 2/3 of the wires is/are spiral and the other wire/s is/are straight. The stretch of the cord under a load of 5 kg is between 0.10 and 0.40%. A method of producing a steel cord comprises supplying a number of element steel wires, forming at least part of at least one of the wires to be spiral, and tightly twisting the wires.