Most bed pillows don"t support the head and the neck. The Original McKenzie® Cervical Roll provides necessary support to the cervical structures and maintains a natural curve of the cervical spine while one sleeps on the side or back. If you suffer from frequent episodes of neck pain; referred pain in the shoulders; nighttime neck problems; or morning pain or stiffness in the neck, your sleeping position may be at fault. Placed between a pillow and the pillowcase, the cervical roll is designed to work with most conventional pillows. It is affordable and portable, and it is not hot and uncomfortable or snug around the neck like a cervical night collar. Made of low density foam with a removable and washable cotton/polyester cover. Size is 3 1/2" in diameter x 20" long. The roll must be used with a very soft pillow (ie; feathers. According to Dr. McKenzie molded rubber or foam pillows should never be used if you have neck problems.This item cannot be returned if the plastic seal is broken.THE MCKENZIE APPROACH TO SPINAL CARE Robin McKenzie has devoted over 30 years developing a system of examination and treatment for non-specific spinal mechanical pain that has been recognized internationally and taught to thousands of clinicians worldwide. Among his accolades, Robin McKenzie is an Honorary Life member of the APTA, a member of the International Society for the Study of the Lumbar Spine, a Fellow of the Society of Physiotherapists in New Zealand and the U.K. and has been awarded the Most Excellent Order of the British Empire (OBE) by Her Majesty the Queen, for "services to Physiotherapy." McKenzie is an accomplished author and journal contributor, and sought-after lecturer. Low-density foam. Latex Free.4"D x 20½"L.