0.125" Diameter x 0.25" Thick Neodymium Iron Boron NdFeB Cylinder Magnet Nickel-Copper-Nickel triple layer coated for maximum protection and durability. Grade N45, stronger than N42, N40, N38, N35, 25% stronger than N35. Magnetized through the Thickness, poles are on the two flat ends. Approximate pulling force: 3.2 lbs