0.375" x 0.066" Thick Neodymium Iron Boron NdFeB Disc Magnet. Nickel-Copper-Nickel triple layer coated for maximum protection and durability. Grade N45, stronger than N42, N40, N38, N35, 20% stronger than N35. Magnetized through the Thickness, poles are on the two flat ends. ISO Certified, These magnets are designed & manufactured to meet the highest quality standards. Approximate pulling force: 4.3 lbs