Used Cisco 7200 Series NPE-400 Processor Memory Modules 

About the Cisco 7200 Series: "Four to six slot routers. Features include support for up to 8,000 concurrent sessions, multi-protocol support, and voice/video/data integration" (Cisco A Beginner's Guide Third Edition by Velte & Velte).

Part # MEM-NPE-400-256MB=

Product Description: 256MB Memory for NPE-400...

Part # MEM-NPE-400-512MB=

Product Description: 512MB Memory for NPE-400...

Cisco 7200 Series Routers
Cisco 7200 Series Processors
Cisco 7200 Series Input/Output Controllers 
Cisco 7200 Series Memory
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