In World War II, the soldiers of the 506th Parachute Infantry Regiment of the American 101st Airborne Division were marked with the spades symbol painted on the sides of their helmets. In this capacity, it was used to represent good luck, due to its fortunate connotations in card playing. Following the confusion of a large-scale combat airborne operation, all four card-suits were used for ease of identification of regiments within the airborne division. Battalions within the regiments were denoted with tic marks or dots, struck from top clockwise: headquarters at the twelve o'clock position, 1st Battalion at the three o'clock, etc.
