Interchangeable Butt Plug Set - Rounded Large - Black. Double your pleasure with this beautifully crafted lightweight butt plug set. Made from high-grade aluminium and silicone this version comes with a large rounded head. together with an interchangeable ergonomic handle and a powerful suction cup! Just take your pick! The large rounded head has a total length of 11cm (4.33). a penetrable length of 8.5cm (3.35) and a maximum diameter of 3.5cm (1.38).