This Chassis ECM Communication Onstar UE1 Opt Upf is a genuine OEM part for a 2011 Chevrolet Malibu. The part number is 591 and the interchange part number is 591-02431. It has a manufacturer warranty of 1 month and is designated as used. This module is designed to work with the Onstar system and is compatible with Chevrolet HHR and Malibu models. It is a crucial component of the vehicle's electronic control system. The inventory ID is C-38-C.