Aer is a device designed especially for urban runners who look for innovative ways to protect their health. It uses mesh technology to turn solution of ectoine into fine mist that can access the lungs entirely. When runners inhale a particular solution of ectoine, it builds a barrier in their lungs by organising molecules of water on their surface. This acts as a defence mechanism, not letting pollution particles through to the pulmonary alveoli. This helps to prevent absorption of pollution particles that have many negative effects on human’s health. Preparing a range of models helped me to get effective feedback from runners. They requested to design something lightweight and shock proof that fits into the pocket. Ectoine is a natural medicine derived from bacteria living in extreme conditions such as deserts or hot springs. As this solution is currently used by Asthmatics, there would be no further human testing required to comply with regulatory standards.