6 Angle hinges, rollers for guide bars, shaft/hub keys for securing shaft/hub connections, hinges, clamping elements in the nature of metal clamps, stands in the nature of metal engine stands, tightening spurs, stop bolts, lockbolts, transmission chains, threaded spindles in the nature of threaded metal studs, guide chains, sections in the nature of metal i-beams, angle plates for fixing metal plates to each other, hinging feet for supporting metal structures, construction elements made of metal in the nature of pendulum supports, shims, securing bolts, clamping devices and quick clamping devices, namely, plugs, anchoring elements in the nature of metal screws, fixing anchors for attaching laboratory tools, bolts, keys for locks, knobs, adjustment knobs, screws, nuts, threaded spindles in the nature of threaded metal pins, rivets, threaded rods, threaded bolts, metering screw, adjustment springs, springs, belleville washers, metal cable wires, screw connectors, tube connectors, manually operated metal valves; all the above products of metal