Steel Grade: T91,T23, T22,T12,T11,T5,T2 etc; Standard: ASME SA213M; Specification: Outer Diameter 16~168.3, Thickness 1~15 Steel Grade: T91,T23, T22,T12,T11,T5,T2 etc; Standard: ASME SA213M; Specification: Outer Diameter 16~89, Thickness 3~16; Application: This product applies to high temperature service such as for super-heaters and reheaters. And the features are precise dimension.