512MB DRAM for Cisco 2901, 2911, 2921 ISR (only as spare)
Cisco MEM-2900-512MB=, 0.5 GB, 1 x 0.5 GB, DRAM
Cisco MEM-2900-512MB=. Component for: PC/Server, Internal memory: 0.5 GB, Memory layout (modules x size): 1 x 0.5 GB, Internal memory type: DRAM