A CPR mask is a medical device used during cardiopulmonary resuscitation (CPR) to provide rescue breaths to a person in cardiac arrest. It is designed to create a seal around the mouth and nose, allowing the rescuer to deliver air without direct contact. This helps reduce the risk of transmitting infections between the rescuer and the victim. Typically made of flexible plastic, a CPR mask often includes a one-way valve that prevents exhaled air from returning to the rescuer. Many masks are also equipped with a strap to keep them in place and may come in various sizes to fit both adults and children.