Wide-Mouth Square Bottle, PP bottle, PP screw closure Square shape saves space, wide mouth is easy to fill. PP is resistant to acids, alcohols and bases. Contactclear bottle provides visible liquid level. Has wide mouth for easy cleaning, sample filling and retrieval. Square shape offers large labeling surface. Autoclavable/Leakproof† . NOTE: Before autoclaving, just set cap or closure on top of the container without engaging the threads.