This development of the familiar 4000 gallon tender had a welded joint between the water tank top and the tender sides and rear. It was introduced from 1947 and allocated to those Black 5s built with roller bearings (44748-67). The familiar tubular air vent pipes were abandoned in favour of a fabrication attached to the rear of the coal bulkhead. The underframe also saw modifications: water sieve boxes were fitted, and the spring dampers shortened. The body curves are preformed.
A listing showing the types of tender first allocated to all the Stanier/Ivatt Black 5 locomotives is available here.
Note that the photo shows the plain bearing equivalent.
Sold as one each of the TB3, TF3 and TC3 packs, at a discounted price.