The Puritan Bennett 540 Ventilator is a reliable, portable, easy-to-use ventilator perfect for transportation or at-home therapy. The 540 Ventilator is designed with patient independence in mind and features lightweight mobility, real time battery life indicator display, tiered audible and visible alarm indicators, and five levels of inspiratory sensitivity and adjustable expiratory sensitivity. The Puritan Bennett 540 Ventilator also incorporates a large, easy-to read display screen and intuitive, menu driven navigation. Return Policy We are accept return within 30-days from the purchase,