Tunnel Snake outfit (Fallout 3)

A Vault 101 Jumpsuit covered on the torso by a Leather Jacket (snake emblem on the back, can be seen on Butch DeLoria or the Tunnel Snakes before taking the G.O.A.T.).

Location
The Tunnel Snake Jacket can be obtained 3 different ways.

1-You can help Butch save his mother from radroaches during the Escape! quest (in any of the available ways). Once they're all dead, Butch will reward you with his jacket. He will also inform you how much he truly admires you, contrary to the harassment he has made the Lone Wanderer undergo over his entire life.

2-Instead of helping him, you can just kill Butch (or watch him get killed by Radroaches, but that's unlikely) and then loot his jacket.

3-You can also obtain this by killing Butch in Rivet City after completing Trouble on the Homefront.