Cheap Titanium Rings ASTM B381 Grades:Gr1, Gr2, Gr3, Gr5 Standards: ASTM B381 Specifications(mm): OD:150-1500mm Cheap Titanium Rings ASTM B381 1. Grades: Gr1, Gr2, Gr3, Gr5, Gr7, Gr12, etc.2. Standards: ASTM B3813. Specifications(mm):OD:150-1500mmID:100-1500mmSection Height: >8mm 4. Package: standard seaworthy wooden box