10415 Kit contains two 10" x 10" pieces of Dynamat Xtreme to be used when mounting your speaker to a metal baffle like a car door or rear deck lid. For proper installation, use Dynamat's Dynaroller tools. Self-adhesive. Contents: (2) 10"x10" (254mm x 254mm) pieces of Dynamat XtremeDynamat Elimiates Speaker Panel Distortion! Even the best new speakers cause speaker panel distortion. Home audio speakers typically come in well crafted, heavy boxes to eliminate this distortion - a solution that is impossible (or at least impractical) in your car. For your car, Dynamat is the solution. Applying Dynamat to the panels surrounding your speakers eliminates speaker panel distortion by transforming the flimsy sheet metal into a solid non-resonant baffle. Dynamat improves mid-bass performance and stops vibration rattles and squeaks. Your stereo will sound its very best with Dynamat. Dynamat Speaker Kits are available in two levels of performance. The Original Speaker Kit offers the best value for the money. The Xtreme Speaker Kit controls vibration four times better than Dynamat Original and requires no heat for installation, which makes Xtreme Speaker Kits a great choice for do-it-yourselfers. Ideal for mounting your speaker to a contoured metal surface like a car door or rear deck.