Product Description Bosch BP990 QuietCast Premium Semi-Metallic Disc Brake Pad Set For Scion: 2012-15 iQ, 2004-06 xA, 2004-06 xB; Toyota: 2003-05 Echo, 2003-05 MR2 Spyder, 2003-09 Prius; Front Amazon.com Today, one of every three Asian, Domestic and European vehicles on the road in North America includes Bosch braking components. That’s because Bosch has been a key player in the braking industry since applying for its first brake system design patent in 1936. Bosch introduced Antilock Braking technology to market, as well as Electronic Stability Control systems. Now Bosch brings over 70 years of OE braking expertise to the aftermarket with Bosch QuietCast Premium Disc Brake Pads. Quiet operation and reliable braking performance QuietCast raises aftermarket brake pad technology to a whole new level. Employing the industry’s best pre-attached, rubber core shims and Molded Shim Technology (on selected applications); QuietCast delivers the quiet operation you expect with the durability and long life that are the hallmarks of all Bosch products. Bosch is the name you can trust every time you put on the brakes.Engineered, Manufactured, Distributed and Backed by BoschBosch is closely involved in every step of the QuietCast process. From a worldwide R&D network with 2,500 associates and nine test tracks, to dedicated engineers that source and rigorously test all friction materials and formulations, QuietCast brake products are manufactured under the same exacting quality standards as OE components and systems. Industry-leading materials with Molded Shim Technology Click to view largerThe Complete Brake Pad SolutionThere’s more to value than just a good price. Value also includes quality, extensive coverage, reliable supply and manufacturer support. And that’s just what you get with Bosch. The QuietCast Premium Disc Brake Pad program offers top quality, availability, competitive pricing and full coverage for all makes and models of Domestic, Asian and European automobiles, light trucks and SUVs. Formulations include platform-specific ceramic, semi-metallic and non-asbestos organic (NAO). The Science Behind the SilenceEvery Bosch QuietCast Disc Brake Pad is fitted with the industry’s best pre-attached rubber core shim. This shim style is the most predominant type used by OE manufacturers and is exclusively offered by Bosch for the independent aftermarket.The laminated rubber-core shim is heat and pressure cured between two layers of steel (see Figure 1, opposite page). This process ensures the highest quality bonding of the rubber to steel resulting in lower noise, increased strength, and corrosion resistance. Sound vibrations pass through the friction material and backing plate, but are dissipated by the unique rubber core in the shim for remarkable noise dampening.About Molded Shim Technology (MST)At the time of pressing, heat, adhesive and pressure mold the multi-layer shim to the backing plate and friction material creating an integrally molded unit. The shim stays attached throughout the life of the pad; it won’t walk or slide on the backing plate, providing maximum stability resulting in quieter shim performance over the life of the pad.