A mattress has a central section. The central section has horizontal upper and lower surfaces. The central section has parallel first and second side faces. The central section has parallel first and second end faces. The side and end faces are vertically oriented. The side and end faces each have a rectangular configuration. The central section has four corner faces located between the end and side faces. The mattress has four similarly configured corner sections. Each corner section has a hypotenuse face positionable in facing contact with an associated corner face of the central section during use. Each corner section has two similarly configured leg faces positionable as planar extensions of contiguous side and end faces.