Silgan Plastics C63530000B01 63mm Self Vented Cap - Critical to every package is how it is sealed — and we can seal it for you. Silgan specializes in both single and multi-piece dispensing and non-dispensing closures and fitments for the food and spice markets. We're also quite proud of our ability to manufacture custom, injection-molded plastic closures and related components to the most detailed, exacting standards and offer you complete packaging options.