Routers/Internet Access Systems DSL Routers ISDN Routers ISDN/Analog Systems		ISDN/Analog Systems 3Com® SuperStack® 3 Remote Access System 1500 ISDN S/T Card Optional two-port digital I/O card for the base or expansion unit (3C421600A or 3C421670A); two BRI S/T-interfaces; handles ISDN and V.90 analog calls Product #: 3C421810A - DISCONTINUED 3Com® SuperStack® 3 Remote Access System Analog V.34 I/O Card Optional four-port I/O card for the base or expansion unit (3C421600A or 3C421670A); provides four built-in V.34 analog modems Product #: 3C426130A - DISCONTINUED 3Com® SuperStack® 3 Remote Access System 1500 T1 ISDN PRI Access Unit Optional one-port T1 module for the base unit (3C421600A); provides 23 built-in ISDN PRI modems; handles ISDN and V.90 analog calls; stackable Product #: 3C433270A - DISCONTINUED 3Com® SuperStack® 3 Remote Access System 1500 Base Unit Integrated ISDN or analog Internet, LAN-to-LAN, and management access; two I/O card slots plus three expansion ports; stackable Product #: 3C421600A-US - DISCONTINUED 3Com® SuperStack® 3 Remote Access System 1500 Expansion Unit Adds two I/O card slots to the base unit (3C421600A); can add one or two of these modules to the base unit; hot-swappable; stackable Product #: 3C421670A-US - DISCONTINUED 3Com® SuperStack® 3 Remote Access System 1500 ISDN U Card Optional two-port digital I/O card for the base or expansion unit (3C421600A or 3C421670A); two BRI U-interfaces; handles ISDN and V.90 analog calls Product #: 3C421800A - DISCONTINUED		DISCONTINUED PRODUCTS If you can't find your product among the categories on the left, try locating it in our discontinued products archive.