diff --git a/csharp/SVGLDLibs/SVGLDLibs/Models/ContainerProperties.cs b/csharp/SVGLDLibs/SVGLDLibs/Models/ContainerProperties.cs
index e973393..27bd9ab 100644
--- a/csharp/SVGLDLibs/SVGLDLibs/Models/ContainerProperties.cs
+++ b/csharp/SVGLDLibs/SVGLDLibs/Models/ContainerProperties.cs
@@ -1,4 +1,5 @@
 using System.Runtime.Serialization;
+using System.Collections.Generic;
 
 namespace SVGLDLibs.Models
 {
@@ -149,6 +150,6 @@ namespace SVGLDLibs.Models
          * User data that can be used for data storage or custom SVG
          */
         [DataMember(EmitDefaultValue = false)]
-        public object userData;
+        public Dictionary<string, string> userData;
     }
 }
\ No newline at end of file
diff --git a/src/Components/API/api.test.tsx b/src/Components/API/api.test.tsx
index cf8ae3f..f8d01e5 100644
--- a/src/Components/API/api.test.tsx
+++ b/src/Components/API/api.test.tsx
@@ -192,11 +192,7 @@ describe.concurrent('Models test suite', () => {
     ],
     CustomSVG: 'string',
     Style: {},
-    UserData: {
-      additionalProp1: 'string',
-      additionalProp2: 'string',
-      additionalProp3: 'string'
-    }
+    UserData: []
   };
 
   it('AvailableContainerModel', async() => {
diff --git a/src/Interfaces/IAvailableContainer.ts b/src/Interfaces/IAvailableContainer.ts
index c973d41..a4067e3 100644
--- a/src/Interfaces/IAvailableContainer.ts
+++ b/src/Interfaces/IAvailableContainer.ts
@@ -6,6 +6,7 @@ import { IAction } from './IAction';
 import { IMargin } from './IMargin';
 import { Orientation } from '../Enums/Orientation';
 import { Position } from '../Enums/Position';
+import { IKeyValue } from './IKeyValue';
 
 /** Model of available container used in application configuration */
 export interface IAvailableContainer {
@@ -161,5 +162,5 @@ export interface IAvailableContainer {
    * (optional)
    * User data that can be used for data storage or custom SVG
    */
-  UserData?: object
+  UserData?: IKeyValue[]
 }
diff --git a/src/Interfaces/IContainerProperties.ts b/src/Interfaces/IContainerProperties.ts
index 11ae73f..35b1db7 100644
--- a/src/Interfaces/IContainerProperties.ts
+++ b/src/Interfaces/IContainerProperties.ts
@@ -3,6 +3,7 @@ import { PositionReference } from '../Enums/PositionReference';
 import { IMargin } from './IMargin';
 import { Orientation } from '../Enums/Orientation';
 import { Position } from '../Enums/Position';
+import { IKeyValue } from './IKeyValue';
 
 /**
  * Properties of a container
@@ -122,5 +123,5 @@ export interface IContainerProperties {
    * (optional)
    * User data that can be used for data storage or custom SVG
    */
-  userData?: object
+  userData?: IKeyValue[]
 }
diff --git a/src/Interfaces/IKeyValue.ts b/src/Interfaces/IKeyValue.ts
new file mode 100644
index 0000000..06a7b0c
--- /dev/null
+++ b/src/Interfaces/IKeyValue.ts
@@ -0,0 +1,5 @@
+/* eslint-disable @typescript-eslint/naming-convention */
+export interface IKeyValue {
+  Key: string
+  Value: string
+}