Cufflinks by Lindsey Mann Due to the nature of the materials used for these cufflinks patterns may vary slightly. Features Primary Material : aluminium Other Materials : silver Fitting Type : hinged bar Dimensions (mm) : 15x15x25 One of a Kind : No Metal : silver Hallmarked : Yes Cleaning InstructionsClean oxidised silver using a mild scotchbrite pad in a circular motion, avoiding contact with aluminium elements. Clean anodised aluminium using a soft damp cloth with some washing liquid.