PRODUCT FEATURES:Chassis provides the foundation for a family of data backhaul productsSupports up to four DS3s, 28 DSX-1 drops, and two optional modules capable of processing up to six additional DS1sHouses two hot swappable controller modules that provide 1:1 redundancy for the DS1 and DS3 interfaces1:1 controller card redundancyHot-swappable controller and module cardsNEBS Level 3 compliant