Aspen® Cervical Collars Pads wick moisture while shell distributes and transfers head weight to shoulders and upper thorax. Fit upright or supine patients. Front and back airflow openings. Adjustable Occipital Support Strap™. Aspen TX includes thoracic extension. Both models include a breathable pad set (front and back) and extra set of replacement pads.Suggested code: L0174 (Aspen TX); L0172 (Aspen).Sizing: Measure from the top of shoulder to bottom of chin and neck circumference. Pediatric: Select appropriate age and measure neck circumference. Age guideline based on normal growth and development.Adult Shoulder To Chin Neck CircumferenceShort less than 5/8" 13" - 21"Regular 5/8" to 1-1/4" 13" - 21"Tall 1-1/4" to 1-7/8" 13" - 21"Extra Tall more than 1-7/8" 13" - 21"Pediatric Age in Years Neck CircumferenceTot 1 - 3 8-1/2" to 13"Child Short 2 - 5 11" to 14-1/2"Child Regular 3 - 6 11" to 16-1/2"