... . Manufacturing Standard: ASTM A554, JIS, DIN,EN, GB.3. Nice raw material from Tisco, BaoSteel, and the other large mills. 4. Grade ... . Hairline:180,240,320. Mirror:400,600 6. Straightness: very nice. 7. Thickness: 0.25mm~3.0mm, strict with ASTM A554 ...