units in the U.S. Army, though most were issued the solid olive green OG107 sateens or jungle fatigues, while the Marines adopted the pattern service-wide after 1968. The ERDL pattern fatigues were identical in cut to the third-pattern OD jungle fatigues, and were available in both a highland pattern (more brown) and a lowland pattern (more green), though the lowland pattern was eventually phased out. Other, unofficial, patterns utilized in Vietnam included black-dyed or spray-painted jungle fatigues, often used by special purpose forces, and various Vietnamese Tigerstripe patterns (themselves being based on French Army airborne and Foreign Legion patterns and a British design utilized in Malaysia), or commercial "duck hunter" patterns. The general design and configuration of the U.S. BDU uniform were similar to that of the Vietnam War's jungle fatigues, which were in turn similar in configuration to specialty uniforms worn by U.S. paratroopers during World War II. History First issued in limited number to garrison leaders, officers, and generals to all branches of the U.S. Armed Forces in September 1981 for replacement of the long worn and aging Olive Drab colored uniforms or OG-107, the following month, the Battle Dress Uniform began field issue military-wide. Since 1981, changes included the addition and subsequent elimination of buttoned waist adjustment tabs, the size reduction of the collar, and refinements in stitching and fit. BDUs were initially only issued in a 50/50 nylon and cotton twill blend called the Temperate Weather BDU or TWBDU. Complaints regarding the heat retention of these uniforms, especially following the invasion of Grenada in 1983, led to the introduction of the Hot Weather BDU, the HWBDU. The Hot Weather BDU coat and trousers were constructed of 100 percent ripstop cotton, in a four-color woodland camouflage pattern. However, after complaints of shorter wear and frayed cuffs, along with requirements imposed by unit commanders to starch the all-cotton uniform for parade, the Enhanced Hot Weather BDU (EHWBDU) replaced the HWBDU commencing in 1996. The EHWBDU's components are made with a 50/50 ripstop nylon and cotton poplin blend. BDUs were printed with infrared-brightened dyes. Near infrared (NIR) Signature Management Technology is used in the uniforms to help prevent detection by NIR Image Converters. These photocathode devices do not detect temperatures, but rather infrared radiation variances. NIR-compliant uniforms use a special fabric that allows soldiers to appear at the same radiation level as the surrounding terrain, thus making them more