CDC Vaccine Card Protector The CDC Vaccine Card Protector ($11 for 3, $13 for 5, 10 for $15) is great for cards that are 4x3 inches. It's made from a durable PVC that can withstand daily wear and tear. It's waterproof, flexible, and has a resealable zipper. Image Source: amazon.com CDC Vaccine Card Protector $11 from amazon.com Buy Now