Set of 10 magnets 8 mm x 8 mm (.315 " x .315") material Neodyium Nickel (Ni) Plated (silver-like shine) Grade: N48 - Extremely powerful magnetic material Pull Force is approximately 9.7 pounds under ideal conditions These cylinders are axially magnetized, so the strong North/south poles are in the center of the flat ends. That makes them easier to stack into a cylinder that to connect side by side. SKU M8X8MMCYL NEODYMIUM MAGNETS ARE NOT SAFE FOR CHILDREN