Mechanical-use rubber products are generally defined by their functional role — sealing, dampening, or transmitting force within machinery or equipment — rather than by composition alone. Customs authorities look at design specifications, tolerances, and end-use documentation; a product marketed as a general rubber part but used exclusively in a mechanical assembly may still qualify, but supporting technical data sheets strengthen the classification position.

Yes. Certain mechanical rubber products, particularly those sourced from China, have been subject to antidumping and countervailing duty orders. Importers should check the current scope of any active orders with the International Trade Administration and obtain scope rulings when the product description is ambiguous.