Eclipse Magnetics M2904ESKM Alnico Horseshoe Magnet, 1" Length x 1-1/8" Width x 5/16" Thickness Horseshoe magnet made from Alnico Grade 5 material, painted Red with a maximum temperature of 550 degrees C Length, width and thickness tolerances of +/-0.045" Come keepered (non-magnetic metal plate) to reduce damage 1-inch length, 1-1/8-inch width, 5/16-inch thickness, 7/8-inch width across the poles and 1/4-inch gap between poles Maximum pull of 2.2 pounds