The first BESA report issued in 1903 recommended designs for a 4-4-0 standard passenger locomotive classified as SP and one for an 0-6-0 standard goods locomotive classified as SG.

[3] A later variant designed with a Schmidt superheater was classified SGS (Standard Goods, Superheated).

These locomotives received larger cylinders with piston valves and larger boilers, as well as a four-axle tender with bogies, as compared to their earlier designs which used saturated steam.

[3] SG class locomotives retrofitted with superheaters were classified as SGC (Standard Goods, Converted).

SGC3 class locomotives were retrofitted with superheaters and were fitted with the Lentz rotary valve gear.

SGC-2 240 was originally used on the Eastern Bengal Railway from 1921 until 1936, by which it had been converted to burn oil.