Planet Audio TRQ693 6 x 9 500 W Car Speakers - 3 Way, Full Range, 4 Ohms

Planet Audio TRQ693. It can be hard like fiberglass, squishy like upholstery foam, protective like varnish, bouncy like rubber or sticky like glue. Impedance: 4 Ohms. Butyl rubber has many different applications.

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