Continuous thread closure allows you to thread smoothly and seal tightly every time. This 24-410 black polypropylene (PP) plastic continuous thread closure has a fine ribbed skirt. It includes a heat induction liner innerseal. These closure types are widely used across Cosmetics and hair products, Craft paints, Adhesives, Food and Pharmaceutical. Note: HI liners have good chemical resistance, and work well with both oil and water based products. They are not compatible with bleach or active hydrocarbons. They work well with inert (low acid) products.