The set includes turned brass barrels
British QF 2-pdr was widely used in many tanks and other AFV:
Crusaders Mk.I/II, Valentine Mk.I-VI, Matilda II, Cruiser Mk. I-IV, MKVII Tetrach, Covenanter, AC1 Sentinel.
Daimler, AEC Mk.I, Coventry Mk.I, Marmon-Herrington Armoured Cars.
It is very simple to use in Your model, and makes it extremely realistic. Simply replace original plastic barrels.
Insert the metal barrel using Cyanoacrylate adhesives.