H&R 2.0″ I.D. Race Springs are made with extremely high tensile strength wire alloy which allows the use of a thinner wire thickness. Manufactured using advanced materials and precision technology in Germany, H&R 2.0″ I.D. Race Springs are crafted from special lightweight (hf) 54SiCr6 spring steel. For any given spring rate, they are on average 15% lighter and have 10% more travel than competitors’ springs. 2.0″ Race Springs are available in 4″ and 5″ lengths and are available in a wide selection of spring rates.