Each magnet is 1.875" x 0.875" x 0.390" and this package comes with 12 of these magnets. Ceramic 5 Block Domino Magnet that is dark gray in color. These are also called Ferrite Magnets and are made mainly of Strontium Carbonate and Iron Oxide. These are relatively strong magnets so not for kids to play with. They can shatter when allowed to snap together just like all hard magnets. And, because of their nature, your fingers might get a little black dust on them from the magnetic materials which easily washes off. There are so many uses for these magnets: crafts, tools, holding things on refrigerator, science projects, magnetic assemblies, etc. You are only limited by your imagination. These have a pull force of about 3.5 lbs. Although they are considerably weaker than rare-earth magnets, they are also less expensive and will work for many applications. There is negligible difference in strength between Ceramic 5 Magnets and Ceramic 8 Magnets. Please keep in mind, this material is very brittle and will most likely have small chips...all hard ferrite magnets are this way.