Being electronically controlled, the Spencer 170 operates as a pressure limited pneumatic unit having an intermittent flow. It is a time cycled device. Both children and adults can make use of this device, owing to its respiratory frequencies and vast array of volumes selections. In spite of the ventilation per minute, the insufflation pressure and the frequency, a unique system accounts for a steady mix of air with oxygen. Even a layman could benefit from the safe use of this device, due to the simplicity in regulation, presence of alarms, lightweight structure and compact design of the product. The non rebreathing valve comes with a special pressure limiting instrument, which proves to be user friendly for both children and adults. In the scenario of the medical ventilation, thousands of ventilators which are used across the globe, establishing a point of reference which is quite trustworthy. Clear and instant reading is facilitated by the design of the control instruments. The indications have been minimized to the essentials and there is a logical positioning of the commands in the correct place.