One of the more common styles is Continuous Thread closures and caps, or CT. Packaging Options Direct offers a wide variety of plastic CT closures which consist of a finish that has one non-interrupted thread that spirals downward toward the shoulder of the container. There are industry standard specifications such as 70-400 or 410. These standards call out critical dimensions and tolerances for continuous thread closures and caps and can simplify the process of matching closure to a bottle or jar. To learn about selecting the correct closure read our blog post. Most orders over $199 qualify for free ground shipping.