Pipes and fitting offered upto 2" are as per CTS standard where as 2½", 3" and 4" are in SCH 80 which are as per IPS pipe size (inch series like aqua gold .) Ø Marked fittings will be shortly introduced. Fitting dimensions given in inch series are equivalent to metric series in mm as given in pipe dimension chart. SCH - Schedule,(Pressure class) SDR - Standard dimension ratio ,(Pressure class)