A liquid filter, in particular for the lubricating oil of an internal combustion engine, having a housing with an inlet and an outlet formed from a housing pot having a substantially downwardly open filter element installation opening and a screw-on cover that closes the installation opening, and a filter element arranged in the housing, sealingly separating the inlet from the outlet. In one embodiment of the present invention, the memory system may include a plurality of logic sections that may be used to facilitate execution of relatively complex atomic read-modify-write operations. It uses a gear reduction system to use the same motor to turn both the plunger shaft and the shaft meant to vibrate the bristles of the toothbrush head.