Material: SUS304, SUS316, CF8M, CF8, 4A, 1.4301 1.4008, BRASS...etc. by forged casting, investment casting, sand casting, and centrifugal casting.* Roundness below 1-1/2" +-0.03 mm * Outside dia. 2"-4" +-0.05 mm, 5"-10"+-0.10 mm