Pip-Boy device, Fallout 3 theme, retro-futuristic design, green monochrome screen, chunky buttons, wrist-mounted, post-apocalyptic wear and tear, rusted metal texture, scratched surface, ambient occlusion, dim lighting, Vault Boy mascot on display, 3/4 view, isolated on a dark background, glowing interface, detailed shadows, atmospheric mood, Fallout universe, iconic gadget, leather strap, heavy-duty construction, nuclear age aesthetics.