|The following is based on Fallout 4 cut content and has not been confirmed by canon sources.|
It provides a Damage Resistance of 0 as well as a bonus of +1 to perception. It appears to have been a piece of "armor" that Nick Valentine would have on him, or possibly drop as a death item, however it is never referenced in the code. On the body it takes up the eye slot like sunglasses. If added to inventory via console, it won't appear in the Pip-Boy.
It is referenced in the Fallout 4 Vault Dweller's Survival Guide as the only accessory capable of using ballistic weave.
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