supply of procurement of tube steel seamless heavy grade nominal bore 15 mm etc...procurement of tube steel seamless heavy grade nominal bore 15 mm etc...,tube steel seamless heavy grade nominal bore 15mm black plain ends to is: 1239/pt-i/2004. amendment no.4 june 2010 ( pertains to mild steel) table 5 and plain ends. outside diameter ( minimum 21 mm and maximum 21.8 mm) wall thickness 3.20 mm, nominal mass of steel tubes ( plain end) 1.44 kg/mtr+ 10%. lenght 06 mtrs. material should be he avy duty seamless pipe, black. conditions: totally rust free from inside & outside, fitte d with protective cap at open ends. [ warranty period: 30 months after the date of delivery ] [quantity tolerance (+/-): 5 %age , item category : normal , total po value variation permitt ed: max 8 lacs ] ] => limited