Features :

• Neodymium iron boron (NdFeB) rare earth magnets
• Grade - N40
• Dimensional tolerance - +/-0.005 Inch
• Plating - nickel-copper-nickel
• Maximum working temperature - 176-Degree Fahrenheit (80-Degree Celsius)

Editor Reviews :

Product Description:
MAGCRAFT brand rare earthy magnets feature the strongest type of permanent magnet available today. Five to fifteen times the strength of common ceramic magnets, rare earth magnets can lift 500 times their own weight in steel.

These magnets are primarily composed of neodymium, iron and boron plated in nickel-copper-nickel for shiny corrosion resistant finish.

This set includes forty 0.25" x 0.125" thick super strong magnets.

Rating : - Very Strong, Very Well-Packaged
What more is there to say? A well-intended family member bought other ¾-inch button magnets from an arts and crafts store for decorative magnets my fiancée and I were including as part of our wedding favors. Sadly, after a single inch of .125-inch plexiglass was included, the magnet was no longer strong enough to hold up a placecard the size of a business card.

Just ONE of these magnets was strong enough to hold up everything, and it has less than a quarter of the volume of the store-bought ones!

As the title indicates, the magnets are reliably well-made and the package ensures they will arrive safely. Buy with confidence.