The CS-305 Single Steel Boned Standard length underbust corset is a Level 1 (moderate curves) waist training corset. The 305 has 12 flat and spiral steel bones and is designed for, but not limited, an average torso length. The top and bottom edge have very little contour. This is a great corset for newcomers to corseting or people with very little natural curve. Works great for providing back and posture support. It is available in satin and leather in several rich colors. Sizes from 18-40.