The Amara headgear is available in two sizes - original and 'RS' (Reduced Size). Both sizes of headgear may be used with any size Amara mask, cushion and frame. These Amara masks are packaged with the RS headgear: Petite Small These Amara masks are packaged with the Original size headgear: Medium Large To check the Amara headgear size: With the mask and headgear assembled for normal use, hold the mask with the cushion facing you Look at the right-hand side of the headgear If the headgear is an RS or Reduced Size, the letters "RS" will be printed under the bottom headgear strap's Velcro tab. If the headgear is a standard size it will not have any letters it will not have any printing on any tabs To check the Amara frame size: Hold the mask with the cushion facing you The word "Amara" is printed on the right-hand side of the frame If the frame is an RS or Reduced Size frame, the letters "RS" will be stamped under the headgear clip area If the frame is a standard size it will not have any letters stamped under the clip This is the headgear only and does not include the headgear clips.