These items are a fully concealed barrel hinge manufactured in brass and available in metric sizes between 8mm – 24mm. The brass cylinders are equipped with a small set screw which expands the cylinder after it is mounted in an appropriate hole. The hinges will open to180º from the closed position.and are suitable for stock sizes from 10mm to 25mm. The cylinders also provide a countersunk area for the inclusion of a brass screw as an alternate mounting method. The cylinders are joined by a series of brass plated steel leaves, although in some of the cheaper versions these are made from brass sheet, and appropriate care should be taken.
pdf: Box Bits 3