Single piece flat design enables fast and easy application with colar coded Velcro closures. X-Ray transparent HDPE material, large chin support, foam padding. Large tracheal opening for intubations, rear ventilation panel. Cleaned easily. 6 different sizes, as sets of 3, 4, 5 and 6 in its special carry and storage bag. or as single pieces. 0720a infant 0720b pedi 0720c low 0720d short 0720e regular 0720f tall 0723 set of 3 0724 set of 4 0725 set of 5 0726 set of 6