The M1165A1 w/B3 Kit combines the M1097A2 four door body with the M1113 ECV Chassis and is used as a Command and Control/General Purpose Vehicle. The M1165A1 w/B3 Kit features the flexibility of removable armor to support mission requirements. The M1165A1 increases performance to a more current configuration and combines the roles/missions of the M1097A2 Heavy Variant HMMWV for Command and control; armor ready. The A1 model designator represents the fact it has Integrated Armor Package (IAP) installed, commonly referred to as “Underbody”.