Repellent Stick

The  is a unique quest-related melee weapon found in Fallout 3 designed to ward off Mole Rats, though it unintentionally has a far more fatal effect on them. It is a simple stick, the tip of which is soaked with an unknown green chemical compound created by Moira Brown in her lab.

Location
This item is obtained from Moira Brown at Craterside Supply in Megaton (or underworld if you destroyed megaton).

Characteristics
The Repellent Stick is a simple wooden stick with Mole Rat repellent on it. The stick is exceptionally effective against Mole Rats, as one hit causes an allergic reaction on Mole Rats, causing their bodies to smoke and their heads to explode in a few seconds, while a second hit will cause the explosion to happen instantly. Do not be fooled by what Moira says when you first get this stick, as it's an experiment gone wrong. Moira will exclaim "Poor little mole ratties!" when she realizes it does more than chasing the Mole Rats away.

Bugs

 * If you convince Moira Brown to give up on the book, she might not take the repellent stick back. You thus cannot drop it because it says it's a quest item. (confirmed all platforms)
 * If you pick the lock on her desk, there is a repellent stick. If you take it when you have already finished the quest, you cannot drop it because it's a quest item. (confirmed PS3 and Xbox 360)
 * It is possible to buy the repellent stick back from Moira directly after giving it back following completion of the quest, without completing the optional objective. The stick appears in her inventory. However, once you buy it, it is treated as a quest item. (confirmed PS3, PC and Xbox 360)
 * if you hit a bloatfly with the repellent stick it will cause the bloatfly to stop its attack and fly away from you after 5 or 6s (confirmed PS3)