... 5. 100% inspection. stainless steel 304,316ISO 9001:2008 Item: straight pipe union, press fittings : Item No.DN/mm (Nominal diameter)Length ... and DN100, including GB 1 and GB 2. GB 1 series is same size as DVGW W534:1995, out diameters are ... 35, 42, 54, 76.1, 88.9, 108mm. GB 2 series is same size as JIS G 3448-1997, out diameters ... this link: http://www.hwsspfp.com/en/download.asp Straight pipe union