diff --git a/power/models/p_vm_instance.go b/power/models/p_vm_instance.go
index 457affd7..31e49515 100644
--- a/power/models/p_vm_instance.go
+++ b/power/models/p_vm_instance.go
@@ -164,6 +164,9 @@ type PVMInstance struct {
 	// The pvm instance virtual CPU information
 	VirtualCores *VirtualCores `json:"virtualCores,omitempty"`
 
+	// VSN id allocated to the Virtual Machine
+	VirtualSerialNumber string `json:"virtualSerialNumber,omitempty"`
+
 	// List of volume IDs
 	// Required: true
 	VolumeIDs []string `json:"volumeIDs"`
diff --git a/power/models/p_vm_instance_create.go b/power/models/p_vm_instance_create.go
index a44538bb..3ad1d277 100644
--- a/power/models/p_vm_instance_create.go
+++ b/power/models/p_vm_instance_create.go
@@ -124,6 +124,9 @@ type PVMInstanceCreate struct {
 	// The pvm instance virtual CPU information
 	VirtualCores *VirtualCores `json:"virtualCores,omitempty"`
 
+	// VSN ID of a retained VSN or specify 'auto-assign' to have a new VSN ID generated.
+	VirtualSerialNumber string `json:"virtualSerialNumber,omitempty"`
+
 	// List of volume IDs
 	VolumeIDs []string `json:"volumeIDs"`
 }
diff --git a/power/models/p_vm_instance_update.go b/power/models/p_vm_instance_update.go
index 56e06295..232b2c70 100644
--- a/power/models/p_vm_instance_update.go
+++ b/power/models/p_vm_instance_update.go
@@ -56,6 +56,9 @@ type PVMInstanceUpdate struct {
 
 	// The pvm instance virtual CPU information
 	VirtualCores *VirtualCores `json:"virtualCores,omitempty"`
+
+	// VSN ID of a retained VSN or specify 'auto-assign' to have a new VSN ID generated.
+	VirtualSerialNumber string `json:"virtualSerialNumber,omitempty"`
 }
 
 // Validate validates this p VM instance update