A safe and secure way to transport your prescriptions is in the black mylar Rx bags. These odor-proof bags include a black backing and an opaque front. Using the zip feature, you may swiftly close this mylar zip bag, or you can heat seal it to make it child resistant. These mylar bags can endure the extreme temperatures of freezing and boiling because of the special lamination procedure. This black mylar Rx bag, which measures 3.4 x 4 inches, can store about 1.0 grams of medication.