Nominal Size	Galvanized Pipe	Stainless Steel Pipe		Copper Tube
	Nominal Size	Nominal Size(SCH)	Nominal Size(SU)	Nominal Size
S10	10A x 10A	10A x 10A	13 x 13	13 x 13
S15	15A x 15A	15A x 15A	20 x 20	20 x 20
S20	20A x 20A	20A x 20A	25 x 25	25 x 25
S25	25A x 25A	25A x 25A	30 x 30	30 x 30
S32	32A x 32A	32A x 32A	40 x 40	40 x 40
Standard	KS D 3507	KS D 3576	KS D 3595	KS D 5301