PEHD. With PP screw cap. Popular, all-purpose Boston round bottles that are highly reliable and durable for long-term use. Ideal for storing, shipping and packaging liquids. Rigid and translucent, with excellent chemical resistance. Can be used with most corrosives. Leakproof. PEHD. With PP screw cap. Popular, all-purpose Boston round bottles that are highly reliable and durable for long-term use. Ideal for storing, shipping and packaging liquids. Rigid and translucent, with excellent chemical resistance. Can be used with most corrosives. Leakproof.