The B352A is a 4 oz natural-colored HDPE plastic imperial round bottle with 24-410 neck finish. The cosmo round, also called bullet round and imperial round, is characterized by its tall and slender build with steeply rounded shoulders. High density polyethylene (HDPE) is marked with the resin identification code of 2. HDPE has a high tensile strength, good resistance to chemicals, good impact resistance, highly rigid, and highly scratch resistant. This item has a 24-410 neck finish. The first number refers to the diameter (in mm), and the second refers to the closure depth, style and thread. This container can be paired with a closure with a matching finish. Natural-colored containers are not actually colored. This is the natural color of the plastic, which is a milky translucent color. This translucent color shows product level, or how full (or, if you're a pessimist, how empty) the container is.