Types:
Plain washers, which spread a load, and prevent damage to the surface being fixed, or provide some sort of insulation such as electrical
Spring washers, which have axial flexibility and are used to prevent fastening or loosening due to vibrations
Locking washers, which prevent fastening or loosening by preventing unscrewing rotation of the fastening device; locking washers are usually also spring washers
Only one you might consider is a locking washer I guess but Im pretty sure the touque and friction on the bolt is enough to prevent the bolt unscrewing