The AET washer was designed specifically for applications where the outer diameter of the washer cannot exceed that of the bolt head. Thanks to the conical form of this washer, the tightening torque is spread evenly in all applications. The serrated surfaces are incrusted into the head of the bolt or screw and also into the surface of the part which is being fastened, forming an immobile unit resistant to loosening if subjected to vibration. This washer is suitable for use with a wide range of screws and bolts. It is very useful for use in mechanical assemblies where a locking function is essential. The elasticity of this washer compensates for axial forces avoiding lateral movement and unwanted grating noises. The AET washer is particularly recommended for use for bolts manufactured according to DIN 74 and DIN 912 due to the perfect fit.