This case has 4 wheels located on the wide edge of the case so it's very stable when being pulled on uneven terrain or sloping surfaces. We also added a telescopic pull handle which provides extra clearance between your feet and the case. The ribs on one face were added to protect the center section that houses the pull handle. Although the basic case is 26"x26"x10", the same inside dimensions as our 10" case, the ribs add another inch to the 10" height of the case for an over the ribs dimension of 11". Technically this case is oversize so you may get charged for it however some airlines ignore feet and ribs when measuring so they accept it without an extra charge. The same 10 inch compression members that are used with our standard case work with this case.
The ribbed side of the case can be seen in the photo below showing the 12" version of this case.