Abstract: A blade device for motor-driven cutter instruments has a one-piece cutter bar with a smooth external edge, a sprocket wheel, an endless chain with chain links which meshes with the sprocket wheel and is guided on the cutter bar, and aligned with its central plane narrow, sharpened cutting elements on the outside of the chain links. One type of chain link is a slider which slides on the external edge of the cutter bar and has a lagging zone which meshes with the sprocket wheel and two passage holes arranged close to its base. The second type of chain link is two opposed trapezium-shaped very thin laminae on both sides of the cutter bar, with corner zones which cover the passage holes in the slider and two pins rigidly laser-connected, which pass through the passage holes.