The Core 4-Way Neck G3-5 is a bio-mechanically precise, four-dimensional neck machine. The flexion and extension muscles of your neck are effectively trained while simultaneously improving movement flexibility in your cervical spine. The neck is supported in a comfortable, horizontal position, which not only reduces the pressure in the area of the upper cervical spine but also increases the strength and flexibility of the entire neck. The fine gradation of the weights in 900 g increments on this device also enables a progressive increase and, thus, fast and measurable progress. Regular training on this device can effectively prevent shoulder and neck tension.