Seals Eastern manufactures close tolerance rubber and "rubber to metal" bonded seals according to customer specifications. We support our customers with knowledgeable service and product support. Our products are characterized by high quality, prompt delivery, and superior rubber formulations. Our more frequently manufactured seals and products include: Precision Molded Elastomer Seals O-rings - AS-568A standard o-rings in addition to any non-standard o-ring for the most demanding service. We mold using individual insert cavities for the tightest tolerance on parting lines available. Large diameter o-rings can be "cut and joined".