Abstract: A capsule for containing a concentrated product to use diluted in a solution contained inside a bottle. This capsule is suitable to be secured to the body of said bottle and is also provided with an undercap (10) suitable to cooperate with a corresponding wall (6) of said capsule (1), so as to form a chamber (8) for containing said concentrated product. With respect to prior art bottles, the bottle according to the invention allows the detergent, disinfectant or other solution to be prepared directly at the time of use, thereby preventing degradation thereof during the storage period.