Quick release, split nut

The split nut is held in the correct distance by a sleeve and a flat spring. When pulling the sleeve upwards, the split nut can be divided at two, with the upper side of it held in place by the flat spring. Then is easy for us to place it on a screw without screw it down. After that we push the sleeve down and with the wrench we tight the split nut and clamp the work (or secure a fixture).