Cisco Network Interface Module - Expansion module - SHDSL x 4 - for P/N: ISR4321-PM20, ISR4351-PM20, ISR4451-X-AXVK9-WS, ISR4461-K9-CAP, ISR4461-PM20
Designed to deliver high-speed Ethernet services over SHDSL access, the Cisco Network Interface Module offers symmetric data rates over one to four pairs of copper wire and supports both EFM and ATM modes.