Dark Zone Chests
In the Dark Zone you can find special chests with the SHD logo on them. These require keys to open so you can get to their loot, which can be gotten by killing NPCs in the dark zone. You also require a certain Dark Zone Rank before you can open specific chests.
Opening a chest will reward you with currency and special loot. Once looted, it will take a while before the chest resets and contains new loot. the exact time is not yet known.