Go to the sizing section in the user guide to determine which frame size is most suitable.
If you are male, start with the standard frame size. If you are female, start with the small frame size.
If you try the standard size first, and the frame sits too close to your ears, size down to the small frame for a better fit.
If the frame is too large, try the small size frame for a better fit.
If you try the small frame first and the frame sits too close to your eyes, size up to the standard frame for a better fit. If the frame is too small, try the standard size frame for a more comfortable fit.
For additional therapy assistance.