A digital passcode for unlocking a security-protected door.
You need to find this passcode, along with Passcode A and Passcode C in order to unlock the security door inside the Aircraft Carrier's Forward Hangar in Chris's Chapter 4 and Ada's Chapter 4.
Aircraft Carrier - Forward Hangar. The code is in the corner of the room where you get separated from your partner and you're forced to fight a Rasklapanje.
Ada - Chapter 4
Aircraft Carrier - Forward Hangar. This is initially dropped by a J'avo in one of the rooms that looks like a small laboratory. However, as you go and pick it up it will be taken away by a Rasklapanje. You need to track this monster down and kill it to reacquire the code.