The heat of battle.

Coleman's biggest customer became the U.S. military. During WWII, its Wichita plants cranked out projectiles for the Navy and parts for B-17 and B-29 bombers. But their most valuable contribution to the war effort was the development of the GI Pocket Stove. The specifications seemed impossible.

The stove had to be lightweight, no larger than a quart thermos, burn any kind of fuel, and operate in weather from -60º to 125º F. Fewer than 60 days after work commenced, Coleman demonstrated a working prototype. And in November 1942, 5,000 of Coleman's little stoves went into battle when U.S. forces invaded North Africa. Credit for ramping up production so they shipped out with the troops goes to another Coleman son, Clarence.

The stoves burned for two hours on a cup of fuel from a jeep or plane. They were carried across every battlefield in Europe and the Pacific. They showed up in tents, foxholes and bombers. An article in the Los Angeles Times stated, "Many a huddle of soldiers got the warmth to survive and fight another day from a Coleman® Stove." In all, over a million were produced.