Our company, Jiangyin Longrun Flange Co., Ltd, has been in manufacturing stainless steel flanges for many years as a high-quality supplier in China with ISO 9001 and TUV Certificarions . We promise to you that all our products are produced by strict processing tests, such as:100% no repair welding;100% PMI(Positive Material Indentification) test;100% flaw detection test including dyp-penetrant inspection, X-ray inspection test, ultrasonic testing and so on;100% demensional and visual inspection;We are ready to tell you that our raw material are supplied by our long-term cooperation partener. Especially, most of our flanges are made of Duplex Stainless Steel such as 304/304L/1.4307other:ASME/ASTM: A182-F304/F304H/F304L/F316/F316H/F316L/F316TI/F317L/F321/F321H/F347/F347HDuplex/Super Duplex: A182-F51/60Alloy Steel: A182-F5/F9/F11/F12/F22We hope you enjoy your experience with Longrun Flange and look forward to your continued business.Irissales3longrunflangewww.longrunflange.com