HP WH161AV is compatible in the following HP Models:

HP ProBook 6500 Notebook PC series

HP PROBOOK 6550B NOTEBOOK PC - WD704ET
HP PROBOOK 6550B NOTEBOOK PC - XB756PA
HP PROBOOK 6550B NOTEBOOK PC (ENERGY STAR) - XP893PA
HP PROBOOK 6550B NOTEBOOK PC (ENERGY STAR) - XP894PA

HP ProBook 6400 Notebook PC series

HP PROBOOK 6450B NOTEBOOK PC - BW185US
HP PROBOOK 6450B NOTEBOOK PC (ENERGY STAR) - XP884PA