Adaptor Rings make it easy to fit the db6501 in 6-1/2 inch and 6-3/4 inch applications;Two-way Butterworth outboard crossover with vented housing, electronic tweeter protection circuit;Woofers feature polymer/mica composite cone with butyl rubber surround, Kapton voice coil former. 6.5-inch component system with pair each of woofers, tweeters, crossovers;25mm liquid-cooled silk/polymer composite dome tweeters with neodymium magnet for clear, detailed highs;Special Shipping Information: This item cannot be returned to Amazon.com. For additional information concerning this policy, please visit our Product Specific Returns Policy Page;6.5-inch component system with pair each of woofers, tweeters, crossovers;Woofers feature polymer/mica composite cone with butyl rubber surround, Kapton voice coil former