Hello there! We are conducting a survey to better understand the user experience in making a first edit. If you have ever made an edit on Gamepedia, please fill out the survey. Thank you!
Command of Steel
25% increased Attack Damage while holding a Shield
Attack Skills deal 25% increased Damage with Ailments while holding a Shield
6% increased Attack Speed while holding a Shield 
Command of Steel is a notable passive skill that grants additional chance to block with a shield equipped. It also grants increased armour rating, evasion rating, and energy shield from equipped shields.
- Mark_GGG (March 13, 2013). "Increased Shield Defenses?". Official Path of Exile Forums. Retrieved July 19, 2013.