Cufflinks by Lindsey Mann Features Primary Material : aluminium Other Materials : silver Fitting Type : hinged bar Dimensions (mm) : 23x15x25 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.