Review on 50Pcs Disney Cartoon Character Stickers - Waterproof Vinyl Decals for Water Bottle, Laptop, Car, and More! by Linda Diaz

My daughter put this on her water bottle and had trouble putting it on, we just kept smoothing it over and over to make it sit flush with the bottle and it looked like this the next morning. Tried flattening them again to no avail. Not sure if there is something in the hydroflask preventing it from sticking but this is their second hydroflask and the other one is covered in stickers and neither of them had any sticking issues. If you see a side view of a mermaid sticker that's completely flush with the bottle, that sticker is from a different set of stickers, no problem with that. Maybe apply a warning not to buy for hydroflask.