Some information about Under The Black Flag Resource Pack 1.7.4/1.7.2/1.6.4 that you can need before installing

How to Install Under The Black Flag Resource Pack for Minecraft

Make sure your  Minecraft is updated to 1.6 or higher Download the resource pack and put it somewhere easily accessible (Desktop) Open up your minecraft from Run appdata minecraft Open the resource pack folder which is inside the minecraft Then just drag and drop your resource pack to this resource pack folder Close everything and enjoy! ...

Detail and Download here : Minecraft mods 1.7.5/1.7.2/1.6.4