diff --git a/lcl/extctrls.pp b/lcl/extctrls.pp
index 53245c7e4c..89c2c0317a 100644
--- a/lcl/extctrls.pp
+++ b/lcl/extctrls.pp
@@ -217,15 +217,15 @@ type
                                              write FOnCloseTabClicked;
     property OnGetImageIndex: TTabGetImageEvent read FOnGetImageIndex
                                                 write FOnGetImageIndex;
-    property OnPageChanged: TNotifyEvent read fOnPageChanged write fOnPageChanged;
+    property OnPageChanged: TNotifyEvent read FOnPageChanged write FOnPageChanged;
     property Options: TNoteBookOptions read FOptions write SetOptions default [];
     property Page[Index: Integer]: TCustomPage read GetPage;
     property PageCount: integer read GetPageCount;
     property PageIndex: Integer read GetPageIndex write SetPageIndex default -1;
-    property PageList: TList read fPageList;
-    property Pages: TStrings read fAccess write SetPages;
-    property ShowTabs: Boolean read fShowTabs write SetShowTabs default True;
-    property TabPosition: TTabPosition read fTabPosition write SetTabPosition default tpTop;
+    property PageList: TList read FPageList;
+    property Pages: TStrings read FAccess write SetPages;
+    property ShowTabs: Boolean read FShowTabs write SetShowTabs default True;
+    property TabPosition: TTabPosition read FTabPosition write SetTabPosition default tpTop;
   published
     property TabStop default true;
   end;