ERX-OCXA256M-MOD
4 PORT OC3/STM1 OR 1 PORT OC12/STM4 OR 4 PORT T3/DS3 ATM LINE MODULE
OC3-4SM-I/O
4-PORT OC3/STM1 SM IOA. WORKS WITH THE OC3/OC12-ATM, ERX-OCXA256M-MOD, AND OC3/OC12-POS LINE MODULES