Originally Posted by
indyfabz
Don’t believe it’s legal to mail flammable liquids.
I think you have to follow the ORM-D labeling and packaging requirements. They vary with flashpoint and amount of the liquid. It is limited to surface and domestic mail only. It is very similar to mailing butane canisters which I have done.
https://pe.usps.com/text/pub52/pub52apxc_011.htm