washers

Ringlike parts placed between a nut or a bolt and a part to be tightened; they distribute the stress.

flat washer

Placed underneath a screw or the head of a bolt, it distributes the pressure while protecting the work surface.

lock washer

Slightly spiral-shaped washer, which acts as a spring to prevent screws from loosening.

internal tooth lock washer

Washer having protuberances on the inside so that a screw tightens securely and will not loosen.

external tooth lock washer

Washer having protuberances on the outside so that a screw tightens securely and will not loosen.