RT Dygert International

When an application requires a non-standard seal due to extremes in temperature, pressure or an unfriendly environment, our team is there to help. We have many choices to assure the correct recommendation.

Quattro Seals™ feature a geometry that provides twice the number of sealing surfaces compared to standard O-Rings. Doubling the number of sealing surfaces allows a four-lobed seal to perform at lower pressures andor with less squeeze than a standard O-Ring. The four-lobed configuration also creates a more stable seal that reduces the likelihood of spiral twisting in reciprocating applications. This is because rather than relying solely on squeeze to achieve a seal, Quattro Seals™ employ both squeeze and deflection to create the seal.

Of the multitude of different O-Ring dimension standards in existence, the most popular in the United States is AS568. Formerly known as ARP 568, and currently maintained by the Society of Automotive Engineers, AS568 lists 369 sizes of O-Rings with corresponding dimensions and tolerances. This standard offers O-Rings in five different cross-sections, with inside diameters ranging from 132" to 26". Tube fitting boss seals are included in AS568 as "-900" series O-Ring sizes, and are intended for use in MS33649 (now superseded by SAE-AS5202) straight thread tube fittings.

RT Dygert works with a tremendous variety of plastics and can also provide expert recommendations for your most challenging applications. The table below describes our most commonly used machined plastics. The information presented here is necessarily general in nature and abbreviated in scope. For more specific information or expert advice, please contact us and speak directly to an experienced materials specialist. Call us at 866-783-8883, or email us at

RT Dygert stocks virtually every seal product you need in virtually every material. This includes a full complement of rubber, machined plastics and standard materials. As you can read in this section’s pages, selecting the right material for a seal is crucial. We offer selection guidance in these pages, however, we also encourage you to contact our expert staff for questions and recommendations.

RT Dygert's 12-compartment O-Ring kits were specially designed for repair, maintenance and prototype applications. The smaller size of the 12-compartment O-Ring kit allows for easy portability, but still provides a useful assortment of O-Ring sizes to tackle a multitude of projects. Each 12-compartment box is manufactured from durable, fracture-resistant polypropylene plastic.