I bought mine off the rubik's cube website
The 4x4 rubik's cube or the Rubik's Revenge
i dont think you can
Thecubicle.us and several other websites (including Amazon) offer 4x4 Rubik's cubes.
you can get it on flipkart , rubiks.com or on ebay
there are actually six, the original 3x3 cube, the 30th anniversary wood cube, the ice cube(clear 2x2 cube), the plain 2x2 cube, the 4x4 cube, and last but not least the 5x5 cube.
The best choice is Rubik's. Don't get a knock-off. You can buy a reliable 4x4 Rubik's Cube online at the website in the sources and related links(below).
Why are you even thinking to ask that question?
You should not take a 4x4, what you need is a camel.
This skills that someone has to solve a Rubik's cube can be used on any size Rubik's cube, whether it be a 2x2 or a 5x5.
go here:http:/www.youtube.com/watch?v=dJRGmNvlCps&feature=video_response
A regular solid body, with six equal square sides., The product obtained by taking a number or quantity three times as a factor; as, 4x4=16, and 16x4=64, the cube of 4., To raise to the third power; to obtain the cube of.