64oz. Single Wall Growler

Does the growler have the Surgeon’s General warning on it? Some states require that on a growler to be filled by a brewery.

Yes, per the manufacturer’s site:
NOTE: Some states require a government warning on a vessel in order for it to be filled by a local craft brewery. Please make sure you do not remove the government warning decal located on the bottom of the growler.

How long does the beverage stay cold?

This is single wall, so not very long. If you’re looking to keep it cold without putting it in a cooler, you’d want the vacuum insulated growler.