Class 4 steel conduit Class 4 steel conduit : Outer diameter:21.3-219mm Wall thickness:0.4-13mm Length:3-12m Standard: BS, JIS, GB, ... ,etc.SEAMLESS pipe : ISO 9001CERTIFICATE. BUTT WELDED FITTING: Production acc. to the standard of GB /ASTM / ASME / DIN / JISASTM B ... Reducers,seamless and welded -Caps, Wall thickness: From Sch5 up to Sch160/STD/XS/XXSMaterial Grades: A403,WP304, WP304L, Wp316, WP316L ...