The Opticonn OTR-1U-C is a cost effective, 4 slot, 1U chassis for mounting any single slot OTR transimitter or receiver in a equipment rack. Clean up the installation by racking up to 4 single slot OTR transmitters or receivers or mix and match in the same chassis. The unit comes standard with a single 90-240 VAC power supply and the OTR insert cards are hot-swappable. The OTR-1U-C also has a quite fan for proper air flow over the OTR insert cards.