- Provides interface for (3) standard loop-start CO trunks- Equipped with (1) 8-conductor interface jack- Must be installed on 082U, 008U, or 000U Cards- Max (1) daughter board per 082U, 008U, or 000U- Max of (4) can be installed in each Chassis (Main & Exp)- Max of (12) can be installed per system- *There is no Power Failure Transfer circuitry