TCalcProp = class(TPersistent)
 private
   fCalcBorderWidth: Integer;
   fCalcDelta: Integer;
   fCalcEditLeft: Integer;
   fCalcEditWidth: Integer;

   procedure SetCalcBorderWidth(const Value: Integer);
   procedure SetCalcDelta(const Value: Integer);
   procedure SetCalcEditLeft(const Value: Integer);
   procedure SetCalcEditWidth(const Value: Integer);
 public
   constructor Create;
   destructor Destroy; override;
 published
   property CalcBorderWidth: Integer read fCalcBorderWidth write SetCalcBorderWidth;
   property CalcDelta: Integer read fCalcDelta write SetCalcDelta;
   property CalcEditLeft: Integer read fCalcEditLeft write SetCalcEditLeft;
   property CalcEditWidth: Integer read fCalcEditWidth write SetCalcEditWidth ;
 end;

 TCalc = class(Tpanel)
 private
   fCalcProp: TCalcProp ;

   procedure SetCalcProp(const Value: TCalcProp );
 public
   constructor Create;
   destructor Destroy; override;
 published
   property CalcProp: Integer read fCalcPropwrite SetCalcProp;
 end;

constructor Tcalc.Create(Aowner: Tpanel);

procedure SetCalcBorderWidth(const Value: Integer);
begin
...
Tpanel(fOwner).Perform(WM_CHANGE, Integer(prBorder), 0)