A few decades ago most manufacturers had their own patent devices for anchoring tendons. They included bars with threaded ends, enlarged ends of wire which passed through holes in thick plates such that the button sat on the plate, wedges, concrete male and female cones gripping a number of wires arranged in a circle, and a toothed conical wedge in a barrel. The cone and barrel systern is now the most commonly employed device for post-tensioning floors and it is available from most manufacturers.