SD bolts are made of 40Cr steel with cold heading process. Through heat treating, the hardness of track bolt can reach 12.9 grade, which is suitable to applications where high wear resistance is critical. Our track bolts are applicable to track groups of excavators and bulldozers including brands such as CAT, Komatsu, Hitachi, Kobelco, Hyundai, etc. With years of experience in bolt manufacturing and supplying, we are large enough to provide you with high quality track bolts and nuts per your drawings and specific needs.