Traditional memory deployed in demanding environments is difficult to expand, is not flexible with space and has limited capacity and specifications. The innovative design of Apacer XR-DIMM memory modules solves these problems. The application area is electronics for automotive, defense and aerospace. The board-to-board connector is a highly durable 300-pin connector with mounting holes to prevent memory modules from dislocating or loosening due to vibration or strong impacts. Oxidation of the contacts when exposed to contaminated or humid environments is also a thing of the past. They comply with MIL-STD-810 and ANS/VITA 472005. The innovative chip design with a wide temperature range and built-in temperature sensors guard against overheating. The underfill and conformal coating excludes moisture, dirt and even sulfur-containing gases. The stackable memory modules is compatible with DDR4 2133/200 specifications are available in 8GB and 16GB.