The picture shows soldiers with gas masks assigned to a company of a combined brigade under the PLA 82nd Group Army in field training exercise. The predecessor of this company was the 4th Company, 239th Regiment, 80th Division under the CPV’s 27th Army. In November of 1950, the 4th company accidentally encountered the Regimental Combat Team 31(RCT-31) of the US Army in Sinhung-ni Region, east of the Chosin Reservoir in northern DPRK. The 4th Company fought tenaciously and destroyed the commanding post of the US Regimental Combat Team 31 and captured its flag. The 4th company was awarded the title of the "Model Company of Sinhung-ni Battle" by the 27th Army.