This is a bag of 100 M3 spring washers. Spring washer are used to prevent components from loosening due to vibrations. Compared to normal washers, spring washer specifically handle shocks and sustain loads better, by providing a spring force.
ReprapWorld is the number one webshop for all your reprap supplies for your 3D printer. We have a large collection of 3D printer components, from our famous electronics lines to filament from our own production. And everything is at a very competitive price!