Promotional 25cm x 20cm Onyx Black Wall Display Plaque inc Fixing Kit The 25cm x 20cm onyx black glass plaque can be engraved with any commemoration details for a building opening or to recognise an outstanding achievement, it can be mounted vertically or horizontally onto a wall internal recommended using the 4 satin chrome fixing stand offs that are supplied with the plaque. The plaque displays best when the engraving is infilled, as shown, the price for infilling is shown in the price list.