Vault 13 Flask

The Vault 13 flask is a miscellaneous quest item in Fallout: Brotherhood of Steel.

Gameplay
A blue flask for holding water, with a number 13 inscribed on it.

Location
Found in the Mill Storage Area, the Vault 13 flask is marked as a "Quest Item" and can only be given to the wasteland stranger in exchange for 100 bottle caps & 100 Experience Points. On receiving the flask, the wasteland stranger remarks on the condition, noting "the old vault colors haven't even faded that much."