Parts list from Cisco for the GSR 12406:

10X1GE-SFP-LC-B                             2
CAB-GSR6-US                                 1
CSS5-GBIC-SX=                               20
GLC-SX-MM                                   2
GLC-SX-MM=                                  2
GRP-B                                       1
GSR6/120-AC                                 1
MEM-DFT-GRP/LC-128                          1
MEM-GRP-FL20                                1
OC192/POS-SR-SC                             1
S120K5Z-12.0.21S                            1