Model 2000 Small Animal Ventilator is designed to be used with animals ranging in weight from 1 to 200 kg. Time cycled: Insures consistent, repetitious, dependable breathing at respirator rates adjustable from 6-40 breaths per minute maintaining the patient at a more stable depth of anesthesia. Volume constant: Insures that each delivered breath will have essentially the volume, independent of changes in patient compliance and airway resistance. Deliverable tidal volume (TV) range is from 20cc to 3,000cc. Pressure limited: Provides for patient safety by limiting the maximum working pressure (MWPL) to a user adjustable pressure range of 10-60cm H2O. Interchangeable bellows: Keyed filling for safer and pollution reduced filling and draining