diff --git a/jquery.gridster/gridster.d.ts b/jquery.gridster/gridster.d.ts
index 9328cc5265..6019ebb067 100644
--- a/jquery.gridster/gridster.d.ts
+++ b/jquery.gridster/gridster.d.ts
@@ -32,8 +32,8 @@ interface GridsterDraggable {
 	limit: boolean;
 	offset_left: number;
 	drag: (event: Event, ui: GridsterUi) => void;
-	start: (event: Event, ui: { helper: JQuery }) => void;
-	stop: (event: Event, ui: { helper: JQuery }) => void;
+	start: (event: Event, ui: { helper: JQuery; }) => void;
+	stop: (event: Event, ui: { helper: JQuery; }) => void;
 }
 
 interface GridsterUi {
@@ -228,4 +228,4 @@ interface Gridster {
 	* @return Returns the instance of the Gridster class.
 	**/
 	disable(): Gridster;
-}
\ No newline at end of file
+}