Aegis

When an attack is made against you, you can use your reaction to expend charges from the magic item Glove of the Aegis. You gain a +2 bonus to your AC for each charge expended. 

Glove of the Aegis - 

This glove holds 5 charges and recharges 1d4+1 expended charges each day at dawn. When a target that you can see hits you with an attack, you can use your reaction to expend any number of the glove's charges. For each charge used in this way you can add +2 to your AC for the attack, potentially causing it to miss. You can use this ability after the attack has been made but before any damage has been calculated.

The glove's power cannot be used if you are already wielding a shield.