1.Upstream location is between the catalytic converter and the engine.Downstream location is between the catalytic converter and the tailpipe2.Durable and long lifespan3. It can the conversion rate of Oxygen in maximum extent4. Perfect aftermarket replacementPlacement of Vehicle:Front,RearManufacturer Part Number: 56028994AA, 56029049AA, 56041698AA, 56044627AA, 56044652AAInterchange Part Number: 23159, SG1849, 234-4587, 15510Length:29inch(2pcs) and 22.4inch (2pcs)Compatible With:For 2005-2012 Ram 1500For 2005-2012 Ram 2500For 2005-2011 Ram 3500For 2010-2012 200For 2005-2012 300For 2007-2009 For 2004-2008 For 2004 300MFor 2004-2012 For 2004-2010 PT CruiserFor 2004-2010 SebringFor 2008-2012 For 2007-2012 For 2008-2012 For 2007-2012 ChargerFor 2004-2012 DurangoFor 2005-2008 MagnumFor 2004-2006 For 2004-2005 For 2004 For 2004-2012 For 2009-2012 JourneyFor 2007-2011 NitroFor 2004-2010 For 2004-2010 ViperFor 2008-2012 CompassFor 2004-2012 For 2004-2012 LibertyFor 2007-2012 PatriotFor 2004-2012 WranglerFor 2006-2010 Colour:Black:Plastic + MetalPackage Contents:4 x Oxygen SensorOnly the above package content, other products are not included.Note: Light and different displays may cause the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.