I noticed a while ago some one was looking for the Proderma Sunscreen mousse that's last 6 hours. I've used the product on my family since it was launched as Bergaderm in the 1990s
If you are looking for it has now been re-branded and improved and is under the name EVY. I get it on Amazon for about £15. It last 6 hours, doesn't wash off and survives towling and swimming. Check out the EVY website. Hope it helps.