Help, I can not get my properties in the constructor PropertyGrid

What is wrong with this? The LeftImage property is not displayed in the PropertyGrid (WinForms.NET 3.5)

    private Image _LeftImage;

    /// <summary>
    /// Sets the small image appearing to the left of the trackbar
    /// </summary>

    [
    Description("The small image appearing to the left of the trackbar"),
    Category("Appearance"),
    EditorAttribute(typeof(System.Drawing.Design.ImageEditor), typeof(System.Drawing.Design.UITypeEditor)),
    DefaultValueAttribute(typeof(Image),"null"),
    Browsable(true), EditorBrowsable(EditorBrowsableState.Always)
    ]

    public Image LeftImage
    {
        private get { return _LeftImage; }
        set
        {
            if (value.Height != 16 || value.Width != 16)
            {
                _LeftImage = new Bitmap(value,new Size(16,16));
            }
            else _LeftImage = value;
            Invalidate();
        }
    }

Where am I wrong ??? The IDE does not complain about anything, and it compiles fine, and all other properties appear in order. Any thoughts?