Patton 1092RC High Speed 2-Wire Synchronous Asynchronous Rack Mount Modem Card

Cisco HWIC-16A 16 Port Asynchronous High Speed WAN Interface Router Card

Cisco HWIC-16A 16-Port Asynchronous High Speed WAN Router Card 73-8972-05

Cisco HWIC-1DSU-T1 1-Port Serial and Asynchronous High Speed WAN Interface Card

CISCO ASYNC-32A 32-Port Asynchronous Serial Network Module NM-32A w/ OCTAL CABLE

🔥 CISCO WIC-2T 2‑PORT SERIAL WAN INTERFACE CARD DUAL SYNCHRONOUS/ASYNCHRONOUS