The Original Backnobber is hand crafted from a manufactured steel bar, bent in the shape of an "S" with wooden balls, one relatively small and one somewhat larger, permanently affixed to each end. The tool is used by hooking the device over a shoulder or under an arm and using its leverage to apply direct, deep, steady pressure to trigger points in the muscles of the neck, shoulders and upper and lower back or any large or small muscle in the body where a trigger point might occur. This pressure followed by careful, regular stretching and strengthening exercises can, over time, significantly reduce muscle tension. The Original Backnobber , the first of its kind, has been a classic favorite of professional, hands on therapists for fourty years. The Regular size Backnobber measures approximately 19 inches in overall length with curves 9 inches across each curve. This size is used comfortably by most small to average sized adults for over the shoulder, deep muscle compression in the neck and upper back areas and under an arm for middle and lower back areas. Colors vary. Proudly made in the USA.