diff --git a/specification/iotsecurity/resource-manager/Microsoft.IoTSecurity/preview/2021-02-01-preview/devices.json b/specification/iotsecurity/resource-manager/Microsoft.IoTSecurity/preview/2021-02-01-preview/devices.json
index 42c426802e0a..961fd2a64396 100644
--- a/specification/iotsecurity/resource-manager/Microsoft.IoTSecurity/preview/2021-02-01-preview/devices.json
+++ b/specification/iotsecurity/resource-manager/Microsoft.IoTSecurity/preview/2021-02-01-preview/devices.json
@@ -643,6 +643,14 @@
         "moduleAddress": {
           "type": "string",
           "description": "Firmware module address."
+        },
+        "serial": {
+          "type": "string",
+          "description": "Firmware serial."
+        },
+        "additionalFields": {
+          "type": "object",
+          "description": " A bag of fields which extends the firmware information."
         }
       }
     },
@@ -716,6 +724,7 @@
         "OtSensor",
         "CorpSensor",
         "Mde",
+        "MicroAgent",
         "Other"
       ],
       "x-ms-enum": {