A sensory deprivation tent, also called a float tent or isolation tent, is a dark, soundproof pod filled with Epsom salt water, heated to skin temperature, that allows you to float effortlessly, removing external stimuli to induce deep relaxation, reduce stress, relieve pain, and promote mental clarity by giving your brain a break from sensory input. Users float in a state of weightlessness in the buoyant, dark, quiet water, which is designed to calm the nervous system.
I last used it a few years ago hoping to be able to put it up in my new place but I do not have room.