Product Description Romsons Cervical Collars are ergonomically designed to support and stabilize neck and spine by limiting the movement of head. These Cervical Collars with Soft Support are highly recommended and trusted by Doctors. Use them for relief from neck pain and stiffness, whiplash or injury.. Size Available: S, M, L, XL SIZE INCHES CM S 3-3.5 7.62-8.89 M 3.5-4 8.89-10.16 L 4-4.5 10.16-11.43 XL 4.5-5 11.43-12.7 XXL 5-5.5 12.7-13.97