The L230H is a white PP plastic 58-400 smooth skirt high lid with F217 liner. This closure includes an F217 foam liner, which will create an airtight seal when the lid is securely screwed on to the container. This lid is made of polypropylene (PP), which means it has a high heat tolerance level and an excellent resistance to fatigue. This closure fits a container with a 58-400neck finish. The first number refers to the diameter of the container's opening (in mm). The second number refers to the thread/style/depth of the closure's skirt.