PoE2
Fire Penetration
Support
Fire
Requires: Level 1
Support Reqirements: +5 Int
Supports any skill that hits enemies, making those hits penetrate enemy fire resistance.
Supported Skills Penetrate 20% Fire Resistance
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
Fire Penetration Support
Fire
Support
Level: (1–20)
Cost & Reservation Multiplier: 130%
Requires: Level (31–70), (52–111) Str
Supports any skill that hits enemies, making those hits penetrate enemy fire resistance.
Supported Skills Penetrate (20–34)% Fire Resistance

Additional Effects From Quality:
Supported Skills deal (0–10)% increased Fire Damage
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.