The main reason is that we don’t want any bulky devices or cables that go from one end of the camera to the other. We think camera accessories like ours need to be unobtrusive and merge with the camera so that you can leave them on the camera the whole time. With this goal, we tried to build a product that would fit on all DSLRs from both Nikon and Canon. However, during the R&D phase we soon realized that this would not be possible, at least not without compromising on key characteristics we wanted the Unleashed to have. This is why the Unleashed is available in a few different versions that will fit perfectly to your camera model: The very same product in slightly different formats.