To whom it may concern,
I'm mdcc_tester (just a pseudonym), and I am a well respected contributor to the london fixed gear and single speed internet forums. I would like to point out that your listing could not POSSIBLY include a 5 speed cassette, and you must have made an error.
Rest assured, we are all laughing at your mistake.
I can only imagine how embarrassed you are.
Why not send them an email: