Difference between pads

I plan on padhacking one of these into an arcadestick for my first time but something troubles me. Here we have gamestop Gamestop.com - Buy Official Street Fighter IV FightPad for Xbox 360 - Xbox 360 selling one for 39.99 . . .then we have Z27 Street Fighter Pad IV 4 FightPad for Xbox 360 Akuma - eBay (item 230514738348 end time Sep-20-10 23:39:48 PDT) on ebay selling for 28. Now the difference in price makes me worry about something im missing, that and the whole z27 thing throws me off. Are they the same pad or is the ebay one a knock off >>?

Same pad.

That is just the Seller’s Item Number.
Look at the rest of the Seller’s items, and you’ll see numbers and letters.

alright, thanks ^^