Stretch The Neck Muscles Better: The double-sided knob is different from other single-knob products, as if hands lift your head up from both cheeks with uniform lifting force, which stretches the neck muscles better than hold the chin up, makes the traction effect better. Different Traction: 3 POWER TRACTION 1) Side knobs adjust the height, stretch the neck muscles. 2) Rotate the back knob to fit the airbag to the neck. 3) Inflating the airbag, powerful Traction Air Belt pulling the vertebrae achieves 20 cervical physiological curvature repair. Effective Traction: Ergonomic of neck traction device helps to improve the blood supply for vertebral artery and brain, promotes cervical physiological curvature repair. Please know that will bring the pain initially because of traction. Using 2-3 times per day help you get longtime relief from pressures of the neck pain, tension, muscles spasms. Applicable: Neck Height: 3.2-4.7 inch, Neck Circumference: 13.7 - 17.5 inch. 1) The doctor recommends traction and stretching of the cervical spine (Diagnosis of cervical spondylosis by MRI, X-ray, or CT). 2) Long-term cervical spine compression pain. 3) Numbness in the shoulders and arms. 4) Hear sound when rotate your cervical spine. 5) Traction the condyles of the cervical spine, not fix. Sturdy & Lightweight: The cervical neck traction device make by ABS + PC, light weight, breathable material is not stuffy, and the upper and lower pads can be removed and washed.