Lab X-19 is a hidden underground lab where the main components from labs X-18 and X-16 were sent, to construct a large scale Rainbow psychic antenna. It is located directly below the surface complex, accessed via a dead-end railway sidetrack behind the Red Forest. It is a large complex, occupied primarily by massive power generators necessary to supply enough energy for the continued operation of the Rainbow emitter, known by stalkers as the Brain Scorcher.