1.Upstream location is between the catalytic converter and the engine.Downstream location is between the catalytic converter and the tailpipe 2.Durable and long lifespan 3. It can improve the conversion rate of Oxygen in maximum extent 4. Perfect aftermarket replacement Placement of Vehicle:Front,Rear Manufacturer Part Number: 56028994AA, 56029049AA, 56041698AA, 56044627AA, 56044652AA Interchange Part Number: 23159, SG1849, 234-4587, 15510 Length:29inch(2pcs) and 22.4inch (2pcs) Compatible with: for 2005-2012 Ram 1500 for 2005-2012 Ram 2500 for 2005-2011 Ram 3500 for 2010-2012 Chrysler 200 for 2005-2012 Chrysler 300 for 2007-2009 Chrysler Aspen for 2004-2008 Chrysler Pacifica for 2004 Chrysler 300M for 2004-2012 Chrysler town & Country for 2004-2010 Chrysler PT Cruiser for 2004-2010 Chrysler Sebring for 2008-2012 DODGE Avenger for 2007-2012 DODGE Caliber for 2008-2012 DODGE Challenger for 2007-2012 DODGE Charger for 2004-2012 DODGE Durango for 2005-2008 DODGE Magnum for 2004-2006 DODGE Stratus for 2004-2005 DODGE Neon for 2004 DODGE Intrepid for 2004-2012 DODGE Grand Caravan for 2009-2012 DODGE Journey for 2007-2011 DODGE Nitro for 2004-2010 DODGE Dakota for 2004-2010 DODGE Viper for 2008-2012 JEEP Compass for 2004-2012 JEEP Grand Cherokee for 2004-2012 JEEP Liberty for 2007-2012 JEEP Patriot for 2004-2012 JEEP Wrangler for 2006-2010 JEEP Commander Colour:Black Material:Plastic + Metal Package Contents: 4 x Oxygen Sensor Only the above package content, other products are not included. Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.