Adjust differential & pinion angle for maximum traction and solid launches. Double adjustable design lets you adjust the arm length without removing them from the car. Heavy duty steel construction virtually eliminates suspension deflection. The street/strip arms use Steeda’s exclusive 3-piece bushings with a hard center section to give excellent control, while softer outer bushing parts allow articulation to prevent binding. Competition arms feature race-quality spherical rod-ends for minimum deflection. Our arms are also available with the bushings for the differential; something the "other guys" don't include with their upper arms. NOTE: Does not fit 1999-2004 Cobra Fits 1979, 1980, 1981, 1982, 1983, 1984, 1985, 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004 Mustang 555-4100$259.95 Choose: Street/Comp Adjustable ArmsTrack Only Adjustable Arms w/Spherical Rod EndsSpherical Rods Ends - No Diff Bushings(-10) www.realspeedauto.com Ph.631-563-7325 All parts listed are for the Ford Mustang unless otherwise noted. Copyright 2018 Realspeed Automotive Inc. All rights reserved.