and Never used Parts. Made by Premium Quality Material. Extremely Aftermarket Part. Easy to install and prefect replacement for parts. Replaces Part number:213-3521, 12589867, 2133521, 10456603, AS10017, 8104566030(Please make sure the Part numbers matches the part you are replacing) Item Name:Knock Sensor Install Type:Direct Replacement Fitment: For the Following Vehicles:4.8L 5.3L 6.0L For 2004 For 2004-2005 For 2002-2006 Escalade, EXT For 2003-2006 Escalade ESV For 2002-2006 1500 1998-2002 1998-2004 2003-2007 Express 1500 2500 3500 1999-2006 1500 2007 1500 Classic, 1500 HD Classic 2001-2003, 2005-2006 1500 HD 1999-2004 2500 2001-2006 2500 HD 2007 2500 HD Classic, 2500 Classic 2001-2006 3500 2003-2004 2000-2006 1500 2500 2000-2006 2003-2004 Trailblazer EXT For 2003-2004 Envoy XL 2004 Envoy XUV 2003-2007 GSavana 1500 2500 3500 1999-2006 1500 2006 GSierra 1500 Classic 2001-2003, 2005-2006 1500 HD 2007 1500 HD Classic 1999-2004 2500 2001-2006 2500 HD 2007 2500 HD Classic 2001-2006 3500 2007 3500 Classic 2000-2006 , XL 1500, XL 2500 For 2003-2007 H2 For 2003-2004 Ascender For 1998-2002 For 2004 GTO Colour:Silver Material:Metal Package Contents: 1 * Knock Detonation Sensor Only the above package content, other products are not included. Note: Light reflection 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.