This cpr faceshield is 6” X 6” with a 1.5” Breathing Tube. The strong valve provides a barrier that will not leak or fall apart during CPR. This provides protection for both rescuer and patient. The built-in, one-way valve provides minimum air flow resistance. So more air gets into the patient. The valve also has zero back flow, with an instant shutoff in reverse direction. Assuring that the rescuer does not get the patient’s exhausted air or vomit in their mouth. The face shield is clear so the rescuer can see the victim’s mouth. It helps prevent biological contamination during CPR as well. Perfect for 72 hour and first aid kits.