Japan & Korea Standard Rail Unit Weight: 37.2kg/m, 50.4kg/m, 73.3kg/m Length: 10, 12m Material: U71Mn good quality Japan & Korea Standard Rail Specification: 37A, 50N, CR73 Unit Weight: 37.2kg/m, 50.4kg/m, 73.3kg/m Length: 10, 12m Material: U71Mn Standard: KSB8106-80, JIS E1101-93