Double Hole Washers

What are the differences between double-hole washers?

spring washers are also locked washers, and are the most used type of spring washers. They have a locking function that prevents fasteners from losing. They provide an axial load that counters vibrate and prevents fasteners from losing.

Plain washers are also called flat washers, and are the most widely used screw fastenerersize, or locked washers. They are both flat anders used for protecting a surface from a damage.