I built these screwless vise clamps from 1/2" sq. x 2.5" cold rolled steel. On each clamp there are two side pins that hold the vise. The pins are are made from 0.25" O-1 drill rod with one end turned down to fit the vise holes and the other end press fit into the clamps. Note the cap screw heads of the M6 screws are turned down to allow these to fit into the counterbores whose diameters are restricted by the 1/2" CRS cross sections. The center clamping screws are not necessary but I added these to allow more options for clamping within the limited space of the Unimat SL1000 milling table. I decided to use the 3/16" sq. CRS side risers instead of millings these as an extension of the clamps. The clamp assembly allows me to quickly align the screwless vise with the milling head.