The new and improved Kinect Frame Kubes are basic connecting cubes that can click together (or not if you pick a quiet version) they can also have sharp edges like the KF3 and KF3Q or their edges can be smoothed out like the KF4, KF4Q, KF5, or KF5Q. There are now newer Kubes such as the KF5 and the KF5Q that are easier to use. And the KF3, KF3Q, KF4, and KF4Q Kubes are still slightly difficult to attach because the hole is the same size as the protrusion (Part that sticks out).