Newer (2017?) Hydro Flask.
Tested in June of 2017.
Newer Hydro Flasks (2017 and newer, based on what I have tested) seem to be consistently lead-free! In 2015/2016 Hydro Flask had offered to replace the older leaded products with a lead-free product, so it might be worth giving them a call to ask for a lead-free replacement if you have an older product!
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