Top quality, made by MRB.  This is for the 3mm version and was used on GP clutches but can be used on any series 1, 2 and 3 to close the gap.  Made in mild steel, colour may vary, but are usually a gold colour.
 For some reason, these are not marked with the MB logo and are slightly thinner at 2.8mm thick
 
Also available in 2mm and 2.5mm thicknesses.
 
Product code: LUMBP0384