Who to bring, and what they bring.

Every spec with its tier and the buffs and debuffs it brings to a raid, from the same data Raid Composition counts. Pick a buff to see who brings it; the specs in your raid are marked.

These rank specs, not items. They say nothing about which helm to wear and are not what the planner's per-slot gear rankings are built from. Wowhead's reasoning for each placement is their own writing and is not reproduced here; follow the link under each list to read it.