Kra'Vak Armor question

Hi,
What does K'V Armor do agents Pulse Torps, Needlebeams, Missiles, Salvo
Missiles, ect?
Thanks
Bye
Stephen
P.S. we have been using rules that stat that weapons to 3/4 damage to
Cruisers
and 1/2 to cap ships, I'm checking to see how others do it.