The search results confirm that the Marson 39302 is a "Thread-Setter Kit w/ Poly-Nuts," also referred to as a "Rivet Nut Kit" or "Nut Setter Kit." It includes a thread-setter tool, mandrels, nosepieces, a wrench, instructions, and assorted Klik Poly-Nuts, all within a molded plastic case. The poly-nuts are designed to create strong, flush, backless attachment points in various materials like thin metal, fiberglass, and rigid plastic, suitable for automotive, marine, and general fabrication applications. It's an SAE-specific kit and designed for professional and DIY use.

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