This is PyroLance fire hydrant gun developed by PyroLance company, based in Florida, USA.

Video: Fire guns spray water through concrete walls, iron doors images 1
PyroLance fire gun.

Extremely high pressure water injection equipment can penetrate concrete walls, or metal doors, to help improve fire extinguishing capabilities, especially in hard-to-reach fires. At the same time, ensuring safety for firefighters, the device will spray water through a small 6mm wide hole to help put out the fire and cool the inside. Significantly reduces the risk of backdraft .

Backdraft is the phenomenon of a sudden fire that explodes and causes a big explosion due to the sudden air access to the fire through ventilation such as opening the door, breaking the wall .