A device for providing pressurized fluid is disclosed, operating of the pressure created during chemical reaction accompanied with effervescence effect that provides the required pressure for operation. The device is made to enable creation of the pressure due to chemical reaction between base and acidic materials, one of them may be provided in the form of a tablet. The device may be operated at virtually any angle with respect to the horizon, it may provide continuous pressurized fluid, pulsed pressurized fluid and one- shot pressurized fluid. The device may be adapted to provide the pressurized fluid in substantially constant flow rate through the entire range of operational pressure inside the device.