Ballistic shield

The Ballistic shield is a special device in BATTLEGROUNDS that fits in your primary slot, it will be available later this year in custom games and in event mode.

Summary
The Ballistic shield can stop and deflect bullets fired at their carrier, but the carrier isn't defenseless, they can carry a pistol in the secondary slot for retaliation. As a added benefit the shield is great for clearing small closed quarters combat areas or pushing with your team because any players behind the carrier can be protected from gun fire as well.

Real-life counterpart
https://en.wikipedia.org/wiki/Ballistic_shield