For those of you interested in the arm wamers, I dug up this:

Quote Originally Posted by SadieKate
Here are the measurements lying flat on the table (length x bicep width):

small: 16 3/4" long x 4 5/8"

large: 17 1/2" long x 5 1/2"
I don't have the measurement for the medium at the moment. I, too, have a medium jersey and long arms. The medium arm warmers are great.