Cisco offers a wide variety of connectivity, expansion and upgrade modules to accommodate the range of application needs in customer networks. The network modules assure customers that they can choose a connectivity solution that fits their requirements. As modular components, they are easily and inexpensively field-upgradeable as customer requirements change.This module contains 2 VOX carrier cards, and one Quad E1/PRI card. VOX carrier cards support 60 channels of voice.