4U Chassis of HSTW-IEL-6800M(4U) Series is designed to enable the installation of industrial optical transmission device as a card type. Dual Power is provided to the 4U Chassis, and it can be replaced with Plug & Plug method. The product reliability is very high, and provides a wide voltage input. It is very suitable for an outdoor environment with KCC standard, industrial standard design, dualized power input, and an operating temperature of -40℃ ~ 85℃.