"Muller reappears with a pair of airman’s boots"

Most infantry boots in World War I were made of cowhide with iron heels, such as the 1917 “Trench Boot.” However, they were not waterproof and only laced up the foot. 

The 1917 and 1918 American airman models quickly became the most common boots worn in the trenches.  These were typically much better quality than those of the infantry. 

It was extremely important to have good, dry footwear: trench foot was very common and could result in the complete disfigurement of the feet.