Specifications include, but are not limited to: One (1) or more refurbished and/or new Zoll X Series heart monitors/defibrillators for the Sevier County Ambulance Service. Weight: 1. Unit shall not exceed 10.6 lbs. (4.82 kg) without battery and paper. 2. Unit shall not exceed 11.7 lbs. (5.32 kg) with battery and paper. Dimensions: 1. Unit must not exceed 10.4 in high x 8.9 in wide x 7.9 in deep (25.4 cm high x 22.6 cm wide x 20.6 cm deep) with handle. 2. Unit must not exceed 8.75 in high x 8.9 in wide x 7.9 in deep (22.2 cm high x 22.6 cm wide x 20.6 cm deep) without handle. 3. Unit must not exceed 615 cubic inches (by volume) without handle. Operating: 1. Unit must be capable of operating in temperatures between 0 to 50˚C. 2. Unit must be capable of operating in humidity between 15 to 95% RH (non-condensing). 3. Unit must be vibration tested to meet EN 1789 for ambulance. 4. Unit must be vibration tested to meet RTCA/DO-160G (multiple helicopter frequencies) 5. Unit must be drop tested to meet IEC 60601-1 and tested at 2 meters 6. Unit must be capable of working at altitudes between -170 meters to 4572 meters (-557 feet to 15,000 feet). Transport and Storage: 1. Unit must be capable of being stored at temperatures between -30 and 70˚C. 2. Unit must be capable of being stored between 15 to 95% RH (non-condensing). Environmental Protection: 1. Unit must have a minimum IP55 rating for water and solid foreign objects. Monitor/Display: 1. Unit must have Tri-Mode display. 2. Unit must be able to change display from ‘color’ to ‘black on white’ (high contrast display for optimal display in bright sunlight) via the push of a quick access key. 3. Unit must have night vision goggle (NVG) display. 4. Unit must be able to display real-time 2-lead ECG on screen. 5. Unit must be able to display static ECG analysis results and real-time ECG on screen concurrently. 6. Unit must be able to display four (4) waveforms. 7. Unit must be able to display large numeric values independent of ECG or waveforms. 8. Unit must have a high resolution color liquid crystal display (LCD) as a standard feature. 9. Unit must have a screen size that is a minimum of 6.5 inches (16.5cm) diagonally. 10. Unit must have a screen with a sweep speed of 25 mm/sec or 50 mm/sec. 11. Unit must have a screen that provides a minimum viewing time of 4.87 seconds.