SM-X-72FXS Cisco 72 x Ports FXS RJ-21 Service Module for 4451-X Integrated Services Router

Upgrade your Cisco 4451-X Integrated Services Router with the SM-X-72FXS Service Module, delivering 72 reliable FXS ports for seamless voice and data integration. This module expands your telephony capacity, enabling high‑density connectivity for corporate PBX systems, VoIP gateways, and legacy analog devices. Its RJ‑21 interface ensures secure, high‑quality signal transmission, while the compact design fits effortlessly into existing chassis, preserving rack space and simplifying installation. Designed for enterprise environments, the SM-X-72FXS enhances call handling, reduces infrastructure complexity, and supports future‑proof communication strategies, making it an essential addition for businesses seeking scalable, dependable voice solutions.