Copper faces with 1mm rolled cooper laminated to a 6mm thick aluminum master lap turned true.Traditional lap for charging with diamond powder,These laps are used for pre-polishing or final polishing and are suitable to use with most types of polishing compounds.They comprise of a disk of copper permanently bonded to an aluminium master lap. Both parts are manufactured in China.The copper disk is 3mm thick and can be re-machined if it becomes damaged, contaminated or worn with used.