Kenwood Excelon KFC-X683C Excelon Series 6"x8" 2-way car speakers at Crutchfield
Dual Electronics - 6" x 8" 4-Way Speakers - DLS574
Kicker DS68 6" x 8" (152 x 203mm) Coaxial Speakers (Pair of Speakers) - Walmart.com
Infinity Primus PR8602cf 5"x7"/6"x8" 2-way car speakers at Crutchfield
Amazon.com: MB Quart FKB168 Formula Car Speakers (Black, Pair) – 5x7-6x8 Inch Coaxial Speakers, 50 Watt, 2-Way Car Audio, Internal Crossover, 1 Inch Tweeters (Grills Not Included) : Electronics
PIONEER TS-A6880R 6 x 8" Coaxial 4-Way Car Speakers 240w MAX Pair | eBay
Amazon.com: 4 x Pioneer TS Series 350W Max 6" x 8" A-SERIES 4-Way Coaxial Car Speakers with Gravity Magnet Phone Holder Bundle (4 Speakers) : Electronics