DIN 128 Metric Curved Spring Lock Washers are a type of split lock washer used with hex head cap screws and hex nuts. Curved Spring Lock Washers are intended to help threaded fasteners from loosening by using of a spring force that is created by the washer between the fastener and the mating surface.
DIN 128 A/B Curved Spring Lock Washers are split bowed spring washers that are said to be more resistant to vibration than split helical spring washers and prevent thrust-induced loosening by maintaining a sufficiently high preload. Since their design is non-helical, they can be used with both right- and left-hand bolted joints. Zinc plated and plain finish (unplated and can rust) spring steel and stainless steel can be supplied.