Introduction: Oxygen sensors are designed to monitor the amount of oxygen that's in your car's exhaust stream, as a marker of efficiency and to confirm the catalytic converters function properly.Feature: Condition: Brand New Warranty: 1 YearSpecification Sensor Type: Heated Pakage Include: 4 pcs (two front sensors and two rear sensors) Location: Downstream and Upstream O2 Sensor Configuration: Direct Fit Connector Gender: Female Wires Quantity: 4 Wire Leads Installation Type: Screw Replace OEM Number: 11781433940, 0258005109, 250-24392, 11781742050, 0258003477, 250-24611,2344672, 234-4672,258003477, 0 258 003 477,ES10899,234-4683,250-24392,ES10857 Application: for BMW 323CI 2000 E 46 M 52 L6-2.5L for BMW 323I 1999-2000 E 46 M 52 L6-2.5L for BMW 325CI 2001-2003 E 46 M 54 L6-2.5L for BMW 325I 2001-2003 E 46 M 54 L6-2.5L for BMW 325XI 2001-2005 E 46 M 54 L6-2.5L for BMW 328CI 2000 E 46 M 52 L6-2.8L for BMW 328I 1999-2000 E 46 M 52 L6-2.8L for BMW 330CI 2001-2003 E 46 M 54 L6-3.0L for BMW 330I 2001-2003 E 46 M 54 L6-3.0L for BMW 330XI 2001-2005 E 46 M 54 L6-3.0L for BMW 525I 2001-2003 E 39 M 54 L6-2.5L for BMW 528I 1999-2000 E 39 M 52 L6-2.8L for BMW 530I 2001-2003 E 39 M 54 L6-3.0L for BMW X3(M/T) 2004-2005 E 83 M 54 L6-2.5L for BMW X3(M/T) 2004-2006 E 83 M 54 L6-3.0L for BMW X5 2001-2006 E 53 M 54 L6-3.0L for BMW Z3 1999-2000 E 36 M 52 L6-2.8L for BMW Z3 2001-2002 E 36 M 54 L6-3.0L for BMW Z4 2003-2005 E 85 M 54 L6-2.5L for BMW Z4 2003-2005 E 85 M 54 L6-3.0L for Land Rover for Range Rover2003-2005 4.4L ONLY FOR manual transmission 2004 for BMW X3 3.0 Symptoms of a failing oxygen sensor includes: -Sensor light on dash indicates problem, -Increased tailpipe emissions, -Increased fuel consumption, -Hesitation on acceleration, -Stalling, -Rough idling. Package Includes: 4X Oxygen Sensor Code:MGGRP Authority IDMXR02FXSY NoticeCalifornia Prop 65 Warning NoticeCalifornia Prop 65 Warning Return Policy All of our items come with a 30-day free return policy. If you need to return, please contact us, let us know the detailed problem and send us some pictures for confirmation. We reserve the right to refuse any returns for objective reasons. Shipping Policy All of our items are shipped free with tracking numbers. Orders will be shipped within 3 working days upon receipt of payment. Most orders will be shipped within 1 working day. In most cases, shipping takes 8-12 working days.