Here's a comparison of the 3 available sizes.

• The new 48 x 24 size is VERY LARGE. IT'S ENORMOUS.
  Only buy it if you are 100% sure it will fit on your table.

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• The 36 x 18 size is perfect for any medium-sized table.
  Up here you can have your keyboard, mouse and headphones without
  no problem.

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• Finally, there are the 18 x 16 cm size, ideal for placing just your mouse on top. But don't let the size fool you; you can rest your entire arm on it while gaming and you'll never feel cramped!