Sir-Chem Dusting Powder 61 is a highly refined nonfluorescent gray magnetic powder used for dry method magnetic particle inspection. Sir-Chem Dusting Powder 61 provides excellent colored contrast on polished surfaces with good particle buildup. It is designed to be used in visible light to reveal medium to coarse discontinuities on fabricated components or weldments such as bridges, pipes, large tanks, machinery, and equipment.