The sink periscope is placed inside a sink inside Barracks 2. It is made from the the sink's two faucet handles. The periscope, after the faucet handles are put together, would then exits out of a water-filled barrel that is placed next to Barracks 2, like a periscope that rises from inside the conning tower of a submarine. It is used by Hogan and his men for when they need to take a quick look around the camp to see what is going on when they are either confined to barracks or inside the compound at night.