"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. Diameter in. 1, Dimensions L x W in. 12 x 1, Height in. 1 1/2, Pulling Power lbs. 30, Material Plastic housing w/nickel plated metal strips, Product Style Holding magnet. Nickel-plated metal strips feature up to 30 lbs. pull per inch"