Alpine optimize their SPS-610 6-3/4" speakers for great range and impressive tone definition, even at low power levels. You can connect these versatile Type-S Series speakers to your factory stereo for an immediate sonic improvement, or hook them up to a powerful aftermarket stereo or amp for increased performance. Mineral-fortified polypropylene cones are exceptionally stiff, yet lightweight, which means they can push out accurate bass and deliver clear midrange. Resilient rubber surrounds help keep the woofer centered for accurate cone movement, reducing distortion. Silk dome tweeters bring out all the details in your music. Grilles are not included — factory grilles are appropriate for most installations. Note: Alpine describes this model as a 6-1/2" speaker. Most manufacturers designate this same frame size as a 6-3/4" speaker. For simplicity's sake we list it as a 6-3/4" speaker. Highlights: 6-3/4" 2-way speakers (pair) includes adapter rings for 6-1/2" openings mineral-fortified polypropy