Certain Dri Prescription Protection 72-Hour is a maximum-strength roll-on antiperspirant formulated with 15% aluminum chloride to help control excessive underarm sweating for up to 72 hours. Designed for people with heavy sweating or hyperhidrosis, it works overnight to reduce perspiration before it starts, providing long-lasting dryness and odor protection. The fast-drying, fragrance-free formula delivers prescription-strength sweat control without requiring a prescription.