I use PreSun Ultra Gel 30. I used to be able to find it in drugstores, but it doesn't seem to be carried anywhere locally (I'm in the northeast), so I switched to buying it online.

I've been buying it here: http://www.dillondist.com/skin-care-presun.htm. The vendor is very responsive, and my order is usually shipped the day I place it. I usually order 3 or 4 bottles at a time... If I'm on the road & I can't find my PreSun, my next choice is Coppertone Sport Sunblock Gel, again at SPF 30.

--- Denise