Check out BattleRealms.cc for more Battle Realms related files.

This tool is command line only, and as such should be run in Command Prompt (Start, run, CMD)

Usage: h2o_unpack <h20 archive location>

for example:
"I:\Users\Admin\Documents\H20_Unpack\h2o_unpack.exe" "C:\Liquid Entertainment\Battle Realms\Models\Models.H2O"