Bracket (v10)

RoundedRectangleShapedCompositeCurve rrscc1 = new RoundedRectangleShapedCompositeCurve(Plane.YZ, 40, 120, 12, true);

SlotShapedCompositeCurve sscc1 = new SlotShapedCompositeCurve(Plane.YZ, 9, 5.25, true);

sscc1.Translate(0, 0, 43);

SlotShapedCompositeCurve sscc2 = new SlotShapedCompositeCurve(Plane.YZ, 9, 5.25, true);

sscc2.Rotate(Utility.DegToRad(90), Vector3D.AxisX, Point3D.Origin);

sscc2.Translate(0, 0, -40);

Circle c1 = new Circle(Plane.YZ, 4.25);

Region r1 = new Region(rrscc1, sscc1, sscc2, c1);

Solid3D ext1 = r1.ExtrudeAsSolid3D(-4);

viewportLayout1.Entities.Add(ext1, 0, Color.YellowGreen);

CompositeCurve cc1 = new CompositeCurve(
    new Line(Plane.YZ, 8, -10, 11, -10),
    new Arc(Plane.YZ, new Point2D(11, -5), 5, Utility.DegToRad(270), Utility.DegToRad(360)),
    new Line(Plane.YZ, 16, -5, 16, +5),
    new Arc(Plane.YZ, new Point2D(11, +5), 5, Utility.DegToRad(0), Utility.DegToRad(90)),
    new Line(Plane.YZ, 11, 10, -11, 10),
    new Arc(Plane.YZ, new Point2D(-11, +5), 5, Utility.DegToRad(90), Utility.DegToRad(180)),
    new Line(Plane.YZ, -16, +5, -16, -5),
    new Arc(Plane.YZ, new Point2D(-11, -5), 5, Utility.DegToRad(180), Utility.DegToRad(270)),
    new Line(Plane.YZ, -11, -10, -8, -10));

Region r2 = cc1.OffsetToRegion(-2.5, 0, false);

ext1.ExtrudeAdd(r2, 275);

SlotShapedRegion ssr2 = new SlotShapedRegion(Plane.XY, 12, 5.25);

ssr2.Translate(9, 0, 0);

ext1.ExtrudeRemovePattern(ssr2, 10, 35, 8, 0, 1);

viewportLayout1.Entities.Regen();