I have two 1080, a 1400, 1900, 2700 and 3000. All the rails have basically the same size guide -- except for the 1900 that came with the ts75, which is noticeably bigger than the others! I actually can't join rails with it , as I find there's too much slop on the other rail after adjusting for the greater width of the 1900, not to mention the bump that happens when I cross from one rail to another.