QF 4 inch Mk V gun
QF 4 inch Mk V gun is a rifled breech loader or naval artillery.
Overview
British naval/anti-aircraft/coastal defence artillery.
In detail
It is associated with United Kingdom of Great Britain and Ireland.
Sources
Each source is named with the standing the house places on it, so the evidence can be weighed rather than taken on trust.
reference work · Reputable secondary · Wikipedia
“QF 4-inch naval gun Mk V”, English Wikipedia, consulted as further reading
Consult the sourcereference work · Reputable secondary · Wikidata
Wikidata, structured authority record Q1740119: QF 4 inch Mk V gun
Consult the source