The Ffestiniog Railway 0-4-0T+T were six 0-4-0T+Tsteam locomotives built by George England and Co. for the Ffestiniog Railway between 1863 and 1867.[1][2] The locomotives were built to two designs: the first four were originally side tank locomotives and are collectively known as the Small England class; the final two locomotives were delivered with saddle tanks and are known as the Large England class.
The designation "T+T" indicates a tender-tank locomotive, which is a tank locomotive with a tender. In these locomotives, water is carried in tanks on the locomotive while fuel (coal) is carried in the tender.
^Kidner, R.W., The Narrow Gauge Railways of Wales, Oakwood Press, c.1960, p. 5