A Belleville washer is a conical disc elastic element that produces elastic deformation under compression to provide a stable high preload. Units may be used singly or stacked in parallel or series to achieve different spring force and deflection characteristics for a given assembly.

Materials offered include spring steel and A2 (304) or A4 (316) stainless steel. Surface treatments listed are black oxide, phosphating and zinc plating. Typical uses include anti‑loosening for high‑strength bolts, moulds, valves, construction machinery and hydraulic equipment, and compensation for thermal expansion or stress relaxation. Confirm size, material and stacking arrangement when ordering.