another widely available nalgene outdoor product is a 650 ml (22 fl oz) "all-terrain" or "bike" bottle. the bottle is made from low-density polyethylene (ldpe), and its screw top has two moving parts — a drinking nozzle that seals until snapped open by pulling on it, and a hinged polycarbonate dome, that when closed both snaps the nozzle closed and protects the nozzle against contamination. unlike traditional nalgene containers, this item can be damaged and potentially ruined by filling it with very hot water.