[[Image:Portal 2 Chapter 2 Test Chamber 03.png|left|300px|Test Chamber 03]]
In the third chamber, [[Chell]] uses a Weighted Pivot Cube and portals to redirect beams to receptacles to open the chamberlock door. A [[Ratmann Dens|Ratmann Den]] can be found in this test chamber, along with an Aperture Science Radio that plays "Exile Vilify". [[Wheatley]] can also be briefly seen after the platform in the center raises up on a rail that runs under the floor.