Qorpak PLC-03648 Natural HDPE Handled 128oz (3,840ml) Square Jug with 38-400 White Polypropylene SturdeeSeal Polyethylene Foam Cap. The Qorpak narrow-mouth square jug has an HDPE body, a polypropylene cap with a polyethylene liner, and a handle. This jug has a narrow mouth for substance control and containment and is used to carry and store large amounts of liquid. The HDPE (high-density polyethylene) body provides low-temperature, impact, and moisture resistance, and transparency. Its square shape is used for space-efficient storage, and for applications that require stability.