The class eventually consisted of seventy-nine locomotives.

The 850 Class consisted of 170 locomotives and was built in 14 lots:

The Class H consisted of 4-6-2 locomotives with 8-wheel, dual bogie tenders.

It consists of 2 locomotives and 9 passenger cars.

The present SMV motive power fleet consists of 3 locomotives.

The train consisted of 2 locomotives and 114 cars, 19 of which derailed.

In 1963 the diesel allocation at Ipswich consisted of 55 locomotives which broke down thus:

The rolling stock consisted of 20 locomotives, 68 coaching vehichles and 455 goods vehicles.

The first of these further orders, made in 1989, consisted of six locomotives, and the second further order, in 1990, was for three.

At peak times up to three trainsets may be coupled together to form a train consisting of three locomotives and nine passenger vehicles.