Plastic inner side is coated by soft foam material. 3 levels of height adjustment possible with security lock system. Trachea opening enables carotid pulse monitoring and emergency tracheotomies. The hole at the back side of the collar allows palpation of the rear cervical area. Plastazote foam material also is radiolucent which allows X-ray, it possible to use CT, MRI. Collar is one piece and it is easy to use.