The ERDL uniform takes its name from the Engineer Research and Development Laboratory, where the pattern was originally developed in the late 1940s. It marked one of the earliest attempts by the U.S. military to create a true camouflage uniform for jungle warfare, though it would not see widespread use until the 1960s.

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Designed for dense, tropical environments, ERDL features a natural, organic pattern made up of greens, browns, black, and lighter highlights. Two main variations emerged during its service life, commonly referred to as lowland and highland versions, each with slightly different color balances suited to varying terrain. The pattern itself would go on to influence later camouflage designs, most notably the M81 Woodland pattern.

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The uniform was constructed with lightweight materials better suited to hot and humid conditions, offering improved comfort compared to earlier, heavier garments. Its practical design focused on mobility and breathability, making it more effective for jungle operations.

ERDL saw its most notable use during the Vietnam War, particularly among reconnaissance units and special operations forces before becoming more widely issued later in the conflict. Its introduction marked a turning point in U.S. camouflage development, laying the groundwork for the patterns that followed.