These spiders are an exact reproduction of the 8" top spider for the Cerwin Stroker 15" and 18" car subwoofers, molded off an original. Correct size, profile, and stiffness. They are lighter in color due to being brand new, however these will darken to tan with age, and also sunlight. (I didn't believe it at first either, but they do) There is a little black around the inner holes, right at the edge. This is because these inner holes were laser cut. It's minor, and covered entirely by the center clamp. The 12" stroker takes the 6.5" top spider (which I also have), but the 15" and 18" car subwoofer models took these 8" top spiders.
 If you have already rebuilt your strokers with the smaller spider, it's actually pretty easy to replace them with these. Since these are the correct larger size, they will sit higher up on the cone. So you can cut off your small top spider (carefully, you don't want to cut too deep and into the cone, but you can cut around with a razor blade a little bit in from the edge, and it won't do any harm to leave the ring from the old spider on there) remove the spider/clamp assembly, put the clamp on your new spider, and glue to the cone right above the old one. And you'll be back to full x-max! 
 22 years on ebay,  mostly Cerwin Vega parts, and 100% positive feedback. Will be packed securely and shipped promptly. Thanks!