This cooler is well made with quality materials. I use it daily as a lunch box with ice packs--and even here on the Big Island, HI--the packs stay frozen all day long. Now about the zipper.The zipper is specialized and makes what appears to be water tight. But it comes with a price: one needs both hands to open and close it--and tons of leverage. I've come to appreciate it because it stops me from snacking while I'm driving!