REI Sunblock SPF 50
Here's what other sites are saying:
Sawyer Stay-Put(R) System 2 SPF 50 sunscreen offers sweat-resistant protection for all your active adventures. Formula is designed to absorb well into skin to provide long-lasting protection. Sawyer Stay-Put System 2 SPF 50 sunscreen is enriched with aloe vera and vitamins. 1 oz. container is perfect for travel and taking on the trail.