The LSWR B4 tank is an ideal small shunting engine for a busy station goods yard or hauling short goods trains along a minor branch line. For many years one was usually outstationed at Winchester, the Hamworthy (Poole) Goods station was another regular duty.
Those further from the Southampton/Poole area may also have grounds for a B4 working a local yard, the Southern Railway trying these engines on the ex-LB&SCR Deptford branch and two being loaned to the GWR in 1941 for use at Pembroke Dock, which was busy servicing the demands of RAF Coastal Command flying boats. A B4 would also seem quite at home on a light railway as an alternative to a 'Terrier'.
The first engines were designed by William Adams, with a further 5 generally similar engines added in 1908 by Dugald Drummond.
These engines remained in service until nationalisation, although withdraws started in 1948 several engines lasted a further 10 years and 2 have been preserved, including 96 Normandy on the Bluebell Railway.
The Dapol model has been carefully designed to allow for the detail changes made to the class over their many years in service, including the two distinct cab spectacle plate designs. A high performance motor and drive train are to be fitted to give good smooth running characteristics as slow shunting speeds. Many separate parts have been designed to provide detail fittings which can be adapted to particular engines and periods.