Used for disconnecting transmission oil cooler lines. The flares on the cooler lines near the fittings prevent access with the original style disconnect tools. The locking clip used in the fitting is different than the standard 'tabs' used on most other applications. The #8021 will clear the flare and disconnect the new style clips with ease. Applicable: [2003-2004] Ford Explorer. [2003-2008] Ford F-150. [2005] Ford Expedition and [2003-2004] Cadillac CTS.