MB Quart XK1-169 6 x 9 X-Line Series 2-Way Coaxial Car Speakers Titanium delivers a superior sound quality over aluminum with a very smooth high frequency with the added benefit of additional output The injection molded polypropylene cone delivers impactful midrange/midbass and is perfectly matched to the butyl rubber Surround for great sound. Flexible piston action UV protected rubber Surround is impervious to temperature swings of very warm and very cold. ".75 (20mm) voice coil" Includes all mounting hardware and grilles