In our initial watertight-zipper test, we noted a small drip from the watertight zipper. It didn’t alarm us because it was so small, but we mentioned it. We were actually impressed that it held the melted ice in to such a degree. However, Yeti is very serious about its Hopper zipper being watertight. The company offered to replace it, saying it guaranteed the zipper to be completely watertight. It’s been on my mind to retest it, and we recently did.
Rather than wait for ice to melt, Boating Lab poured water into the cooler and turned it upside down. At first, it did look like it leaked as we observed. We did it again and it leaked again, and then we noticed that it quit after the first few drips.
So, we poured a half-gallon of water into the cooler, zipped it tight, shook it and turned it upside down to shake more water off the zipper teeth, and then we set it upside down over a bucket. Voila. No leakage. After four days, still no leakage.
What happened in our original test was this: As we filled the coolers with “wet” ice, the teeth held small amounts of water, which dripped off for a few moments during our test.
So, we proved Yeti’s claim: The Hopper zipper on our test model was utterly watertight. Congrats, Yeti, on another great product!