A large number of well maintained Chinese Type 63 twin barrel 37mm AA gun at the K91 Warehouse under the Hanoi Capital High Command. The Chinese and Soviet 37mm AA guns played a major role in the air defence network over North Vietnamese airspace during American bombing campaigns since the early stages of the Vietnam War.
Despite being outdated, the 37mm AA guns are still useful against enemy low-altitude targets such as helicopters, incoming slower moving aircrafts, UAVs, and airborne troops.
(VietDefense)