First Defense Nasal Screens are great! Applying the screens was simple and easy. The adhesive works well. I have oily skin, so I wasn’t so sure the screens would adhere well. The nasal screens are also comfortable. I used a pair today because I have a neighbouring co-worker who loves to wear perfume heavily and does not care if it makes the rest of us sick. The nasal screens reduced the smell of her toxic perfume by a lot, so I did not get a headache or become nauseous. I will test the nasal screens again when I go for a run. I love this product as I cannot wear a face mask. Face masks trigger my allergies. Thank you for your ingenuity.