PoE2
Knockback
Support
Requires: Level 1
Supports any skill that Hits enemies, causing it to Knock Back enemies.
Place into a Skill's Support Gem socket in the Skills menu to apply its effects to that Skill. You cannot have multiple copies of the same Support Gem socketed at the same time.
PoE1
Knockback Support
Support
Level: (1–20)
Requires: Level (8–70), (18–111) Str
Supports any skill that hits enemies.
Supported Skills have (25–44)% chance to Knock Enemies Back on hit
Supported Skills have 50% increased Knockback Distance

Additional Effects From Quality:
Supported Skills have (0–10)% chance to Knock Enemies Back on hit
This is a Support Gem. It does not grant a bonus to your character, but to skills in sockets connected to it. Place into an item socket connected to a socket containing the Skill Gem you wish to augment. Right click to remove from a socket.