If you purchase AC adapter itself as additional parts without SN of T550MXP with valid service contract, it only come with Cisco Hardware Warranty (90 days DoA cover).
Customer may purchase PSU-CAM-V= is and contact Cisco service department to update T550MXP service information for including newly purchase AC adapter, and then AC adapter will cover by service contract on T550MXP.
Please contact your Cisco sales representative if need more detail information.
