Introducing the ToughArmor MB604SPO-B ruggedized mobile rack for hot-swapping 4x SATA/SAS SSDs and HDDs up to 9.5mm in height, and 1x Slim 12.7mm or Ultra-Slim 9.5mm CD/DVD/Blu-ray ROM optical disk drive reader for the external 5.25" bay. Featuring industrial full-metal construction inside and out, and designed for commercial applications such as military and medical systems, airborne and shipboard PCs, in-vehicle systems, servers, workstations, and mobile computer systems. Maintain optimal drive temperatures with the user-configurable 40mm cooling fan and plenty of ventilation holes throughout the enclosure. Advanced removable trays with anti-vibration protect drives in harsh environments, and built-in individual status LEDs give you drive updates at a glance. Maximize Space-Efficiency The high-density design of ToughArmor MB604SPO-B packs four 5mm-9.5mm 2.5" SSD/HDD hot-swap bays and one Slim/Ultra-Slim CD/DVD/Blu-ray ROM optical disk drive into a single 5.25" drive bay, perfect for space-sensitive applications such as powerhouse PC, portable military workstation, and rackmount industrial PC. MB604SPO-B''s newly designed optical drive bracket features an adaptable design to support any Slim 12.7mm or Ultra-Slim 9.5mm CD/DVD/Blu-Ray ROM optical disk drive reader. MB604SPO-B''s tray is designed to support HDDs and SSDs up to 9.5mm in height, making them compatible with SAS drives as well as SATA drives. SAS drives are used in enterprise applications such as long-term archival for their long lifespan, higher reliability, and faster rotational speeds up to 15,000 RPM for fast data access. Designed for Versatility Whether you''re using a slim or an ultra-slim disk drive, installation is easy using the conveniently labeled screw holes. Once connected, simply secure the built-in screw and your drive is locked into place. This ensures that your optical disk drive reader stays put, even under heavy movement or vibrations. When using an Ultra-Slim (9.5mm) optical reader, the included foam spacer can be installed on top of the ODD for a cleaner look. When it''s time to replace or upgrade your CD/DVD/Blu-ray optical disk drive reader, removal is just as easy. When the bracket screw is loosened, the spring-loaded ejection arm is revealed. Simply pull the ejection arm to remove the optical disk drive from the enclosure. Built Tough ICY DOCK''s ToughArmor uses a ruggedized full-metal construction throughout the enclosure and trays, and this trend continues with the MB604SPO-B. ToughArmor is specifically designed for industrial applications operating in strenuous conditions, such as in military and medical applications, avionics systems, factory and warehouse machinery, and any application requiring a flammability rating. Packed with Features To prevent the build-up of dust, which over time can clog internal connectors and inhibit airflow, the included dust cover protects the enclosure when an optical drive is not in use. When you''re ready to install an CD/DVD/Blu-ray optical disk drive, the dust cover is easily removed without tools or screws. Individual LED lights for each bay give you drive status updates at a glance, letting you know when your drives are powered on or in use. A user-controllable 40mm cooling fan works with the ample ventilation holes in the tray and chassis to remove as much heat as possible and keep drives running at optimal temperatures. The fan can be set to high for intense mechanical HDD applications, low for use with cooler SSDs, and can be shut off completely to be cooled by the computers built-in cooling system.