33/400 CT (continuous thread) Black Ribbed PolyCone Lined Phenolic Cap. These caps are designed to form an exceptionally tight seal. The PolyCone liner is made of an oil-resistant plastic, offering a superior chemical barrier. This cap fits any of the containers under the Product Accessories below. Jars are sold separately by case quantity. Lids are sold by the piece or case. Scroll down to the From the Blog section to learn more about our Amber Bottles, Lids & Droppers.