Replacement frame for the Respironics DreamWear Nasal, Nasal Pillow, and Full Face Mask. The medium size fits 85% of our patients.The Frame is available in 3 sizesSmall #1116745 (19 inches in length) Medium #1116746 (20 inches in length) Large #1116747 (22 inches in length) The frame size is equivalent to the distance around the head from one side of the nose to the other. Follow these steps to determine the appropriate frame size: Begin by placing the measuring tape marker at the base of the nose on one side. Use the tape to follow along the side of the cheek and upward over the top of the head. Keep pulling the tape measure around the face, down the other cheek, and to the base of the nose on the opposite side.