For Paccar MX13 EPA21 Diagnostic Cable For Kenworth T680/T880, Peterbilt 579/567
For Kenworth: T680, T880, W990 (Models with MX13 EPA21 Engine). For Paccar MX13 EPA21 ECM 2021+. For Peterbilt: 579, 567, 589 (Models with MX13 EPA21 Engine). This cable is designed for EPA21 compliant ECMs.