The Original Jacknobber II is an elegantly designed hand held massage tool that can be used to provide a most pleasant and relaxing back massage. The knobs at each of its four points can be used in many ways to apply deep pressure to muscular trigger points.The smaller knobs provide deeper more intense pressure. The larger knobs provide broader gentler pressure.Use one knob at a time to press deeply into imbedded trigger points; use two knobs at a time on either side of the spine. Arguably the most satisfying hand held massage tool available.