"Powerful Master Magnetics magnetic assembly helps organize ferrous metal tools, utensils, knives, scissors, keys, screwdrivers, wrenches and more. Screw mount style is ideal for shop, kitchen, office or garage use. Material Plastic housing w/nickel plated metal strips, Diameter in. 1, Height in. 1 1/2, Dimensions L x W in. 12 x 1, Product Style Holding magnet, Pulling Power lbs. 30. Nickel-plated metal strips feature up to 30 lbs. pull per inch"