I got these ear mitts in size Regular because I have normal size ears.
They fit perfectly with room to spare but when I "click" them into
position to make a snug fit, I find that after a short time they
cause discomfort behind my ears.  I must say that I do have very
sensitive ears and these may not bother others like they bother
me.  To get around this, I just don't "click" them into position.
This way they rest lightly on my ears and no problem.  However,
if you were going to wear them in very freezing and windy weather,
you would need to make them snug so they provide maximum warmth
and don't blow away.  They're really cute and well-made and come
in their own little pouch.  Not bad for the money, it's just that
my super-sensitive ears don't like snug things on them.