Bilstein B8 Performance Plus (DampTronic) Suspension Strut Assembly for 2005-2011 Porsche BoxsterBilstein B8 Performance Plus (DampTronic) Dampers for the 2005 2011 Porsche Boxster are a performance upgrade to OE Dampers designed to be paired with aftermarket lowering springs. All of the active features of the factory electronic suspension, along with the factory controls, will be retained with the installation of these Dampers. Each damper is rigorously tested for quality that meets or exceeds OE standards and features application specific valve