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They are used in the same applications as fender washers. A spherical washer is part of a self-aligning nut; it is a washer with one radiused surface, which is designed to be used in conjunction with a mating nut in order to correct for up to several degrees of misalignment between parts.
Belleville washers are conical, spring lock washers that exert pressure equally around the washer. They can be used on both the nut and the head end. Tooth lock washers have sharp points that dig into the screw (or bolt head) or the surface to be joined. They can leave scratch marks.