New York Times and other media as well as medical professionals have come out strongly opposed to ultra high spf products above the mid 40's. Many countries around the world limit sunscreen levels to between 30 and 50.  It is scientific fact that going from SPF44 to SPF100 will yield less than 1% additional protection, and you expose yourself to a significant amount of unnecessary chemicals. Their recommendation is to buy in the SPF40 range and find one that stays on.

SolRx Sunscreens are certified 8 hour waterproof in independent tests carried out by AMA Laboratories NY. SolRx product SPF ratings are measured AFTER 8 HOURS, 6 of which are in the water.  Mass market and cosmetic brand sunscreen spf ratings are measured after only 40 minutes and 80 minutes, and per their label instructions, must be reapplied frequently throughout the day.