1.Highly quality control and strict surface roughness test 2.ISO9001:2008, CE,TUV certified. 3.DIN,SMS,ISO,IDF,AS,BS,RJT,BPE Wafter Check Valve(ball type check valve)1.SIZE:DN15,20,25,32,40,50,65,80,100.2.MATERIAL: AISI304L,AISI316,AISI316L.3.STANDARD: DIN, SMS, ISO, IDF, AS, BS, RJT, BPE.