Arcane Shield

Physically it looks like a metal gauntlet, whit and arcane core at the center. Thanks to that core, it is possible to deploy it.

While you wear this shield, you gain +2 AC.

If a projectile passes through a cube of 30 ft centered in you, you can use your reaction to deploy the shield and block the projectile. 

Shields require the Utilize action to Don or Doff. You gain the Armor Class benefit of a Shield only if you have training with it.