4x0 Expansion Card for MacroSMB

This expansion card adds 4 additional CO (trunk) lines, and, NO local extension ports to your MacroSMB system. The MacroSMB can accept up to 9 of these depending on what other cards are used. The system has 10 open slots, 2 are typically reserved for high speed digital cards, which leaves 8 for extension cards and CO line cards.