The BOS_3.1 file you have requested: Maps Levels Missions / BOS 3.1 - 33.87mb is not available. Perhaps try browsing all files for the game ARMA: Armed Assault and upload any files you want to share or are missing. This is the only information we could locate:
ArmAeditor extra by Karhu. It adds ber many bases, control station, lets sy... the sahrani comes alive! Everywhere is everything!