4006 - Other forms (for example, rods, tubes and profile shapes) and articles (for example, discs and rings), of unvulcanized rubber:

This HTS category, 4006, encompasses unvulcanized rubber that has been processed into various shapes beyond raw or basic forms. It specifically includes rods, tubes, and profile shapes of unvulcanized rubber, as well as manufactured articles such as discs and rings derived from this material. The key characteristic of items within this heading is that the rubber has not undergone the vulcanization process, which imparts elasticity and durability.

Category 4006 is distinct from other headings within Chapter 40 by its focus on pre-formed, unvulcanized rubber articles. For instance, it is differentiated from headings that cover raw rubber (e.g., 4001) or vulcanized rubber articles (e.g., headings in Chapter 40 dealing with tires, hoses, or molded goods). It also stands apart from headings focused on specific rubber-based products like footwear or surgical gloves, even if those might utilize unvulcanized rubber in their initial construction phases. The "unvulcanized" state is the primary differentiator.

Within HTS 4006, further subclassification is provided. HTS 4006.10 specifically addresses "Camel-back" strips, which are designed for the specific purpose of retreading rubber tires. All other forms and articles of unvulcanized rubber not covered by 4006.10 fall under the residual subheading 4006.90. This allows for the precise classification of a wide range of shaped, unvulcanized rubber items beyond those designated for tire retreading.