New Tri-Seal Gasketless Openhead Plastic Pail Covers produce a water- and airtight seal without a gasket. Ideal for foods, paints, adhesives, lubricants, building products, consumer products and more, it can be used anywhere a typical gasketed cover is used. No special capping equipment is needed. The cover works with standard rigid-plastic pails and is a drop-in replacement for a standard gasketed cover on most filling lines. The molded cover comprises a primary inner plug "cork" seal that is unaffected by changing top loads, a secondary top "flap" seal that engages the lip of the pail, and a tertiary outer "stretch" seal for added security. The cover is environmentally friendly, and is available in multiple shapes and sizes.
Source:
http://www.packagingdigest.com/article/522973-Pail_covers.php
