Durable single wall Borosilicate glass Solid screw on lid with carrying strap Easy fill wide opening Hand wash only Bottle has the ability to withstand extremely hot temperatures without breaking but will be very hot to the touchTo prevent burns we do not recommend using for hot liquids Packaged in reinforced protective cartons for no additional charge If the bottles do happen to break Borosolicate glass will not shatter into shards or sharp pieces like traditional glass Instead it will break apart into chunks