Collar adjusts to infant, pediatric, and small-adult neck sizes with 12 settings as well as the 3 standard sizes (infant, pediatric, and neckless). Mini ACE incorporates latches allowing rescuer to size collar to victims exact neck size. Safety buttons hold the collar in place for maximum reliability. Stores completely flat. Features include number and color sizing system, flip chin-piece for easy airway access, and nasal cannula tubing holder.