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 your currently equipped weapon, up to a maximum of 100%. Since you cannot usually find normal "Earth-made" weapons aboard the ship to salvage for repairs, it's important to use to repair your normal weapons should you choose not to use alien weapons. The percentage repaired depends on the player's repair skill:

Alien epoxy comes in tubes and over 100 tubes can be found around Mothership Zeta. Since they have no weight, all tubes found can be carried around. While the effect of one tube may not conform to the table above, you can always increase a weapon's condition to 100% by applying multiple tubes one after the other, regardless of your repair skill, which makes alien epoxy perhaps the most significant item which you get from the Mothership Zeta add-on. Because of that, do not sell any epoxy tubes - they have much more value in the field, when guns need fast repair (especially fragile guns like the Gauss rifle and the alien blaster.)

Alien epoxy cannot repair armor or clothing. It increases your DR (damage resistance) by 10 points for 1–12 hours, though.

Behind the scenes

 * An "epoxy" is a step-growth thermoset polymer that solidifies around the applied area. This fits, suggesting that the epoxy fills in cracks or faults in the weapon.