PoE2
Additional Accuracy
Support
Attack
Cost Multiplier: 110%
Requires: Level 1
Support Reqirements: +5 Dex
Supports attack skills.
Supported Skills have 20% more Accuracy Rating
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
Additional Accuracy Support
Attack
Support
Level: (1–20)
Cost & Reservation Multiplier: 110%
Requires: Level (8–70), (8–48) Str, (11–70) Dex
Supports attack skills.
Supported Skills have +(74–1034) to Accuracy Rating

Additional Effects From Quality:
Supported Skills have (0–20)% increased Accuracy Rating
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.