Maximum Damping We offer the optical tops, 784 series with a 5 mm thick top skin out of stainless steel. They have M6 threads in a 25 mm hole pattern with patented Clean Top II individual nylon cups under each tapped hole. Since no penetra­tion of the core is possible when dangerous chemicals are used on the top's surface, health hazards will not occur by chemicals reaching the core unnoticed The table tops are available in a full range of sizes and have the maximum dry damping level. Clean Top II exceeds all current industry standards for structural stiffness and damping. The table tops 784 series are recommended for measurement applications in industry, research and developement. They should be used in interferometrical and holographical experiments where resolutions below 1 micrometer are necessary.