Alien Epoxy (Fallout 3)

Alien epoxy is an item which is added to Fallout 3 in the Mothership Zeta add-on.

Uses
It can be used to increase the condition of the currently equipped weapon, up to a maximum of 100%. Earth weapons are extremely rare aboard the ship, so the epoxy is the only alternative to repair weapons you brought with you. The percentage repaired depends on the player character's repair skill:

Alien epoxy comes in tubes and over 100 tubes can be found in Mothership Zeta. Since they have no weight, all tubes found can be carried without being over-encumbered. While the effect of one tube may not conform to the table above, it is always possible to increase a weapon's condition to 100% by applying multiple tubes consecutively, regardless of a character's repair skill.

Alien epoxy cannot repair armor or clothing. However, it does increase DR (damage resistance) by 10 points for 1–12 in-game hours.

Behind the scenes
An "epoxy" is a step-growth thermoset polymer that solidifies around the applied area, such as glue.