John Crane Packings are designed, engineered and constructed for specific services and applications. This is your assurance that John Crane Packings will provide the best sealing with the least amount of maintenance and adjustment. All John Crane mechanical packings are made of asbestos-free materials. These asbestos-free packings can be substituted without any difficulty for asbestos packings in present use. They can be interchanged with most asbestos products, and in many cases will give better, more dependable performance.