This locknut secures bearings and associated components on a shaft by clamping against a locking washer, transmitting axial force through a threaded connection rather than relying on an interference fit alone. Main dimensions follow DIN 981, with a width of 4.0 mm and a net mass of 7.0 g, making KM1 suitable for the smallest shaft diameters within this locknut series. Used together with a matching locking washer, KM1 allows controlled axial positioning and locking of bearing inner rings mounted on threaded shaft seats. The design permits disassembly and re-tightening without damaging the thread, which is useful where periodic adjustment of bearing preload or axial clearance is required.