Deflection is a Hunter (second tier Survival tree) talent. The talent grant a 1% increase to parry chance per point spent.
For non-tanking classes, usefulness of this talent can be highly varied, depending on spec and preferred play style. This talent is useful for any who plan to PvP, in addition to:
Hunters who are willing to 'off-tank' temporarily while a trap cooldown runs out, or who want to be able to handle a mob a little longer in a group when pulling it off a caster until the tank or the Hunter's pet can pick it up. This talent is often taken in combination with Deterrence and Counterattack.
Patch 1.7.0 (13-Sep-2005): Will now increase parry chance when using Fist Weapons.