CMS Magnetics N45 2x2x1/4" Neodymium Magnet One Piece Powerful Permanent Magnets: Strong Holding Power, Grade N45  48 lb Per Magnet with Direct Touch and Direct Pull, 13,500 Internal Gauss; Great Strength for its Size Muli-Purpose: Great for Stud Finding, Science Projects, Home Improvement, and Much More! Best Coating Available: Ni+Cu+Ni Triple Layer Coated; the Best Coating Available Top Quality: This is the BEST Quality Magnet Made under ISO 9001 Quality System. All Tolerances are +/-0.002 <span class="a-text-bold">Material:</span>Sintered NdFeB. Grade N52 <span class="a-text-bold">Gauss Rating:</span> 14,400 Gauss. <span class="a-text-bold">Pulling Force:</span>90 lbs <span class="a-text-bold">Pole Orientation:</span>Magnetized through the thickness,the poles are on the 1-1/2&#034; x 1-1/2&#034; surfaces. <span class="a-text-bold">Coating:</span>Ni+Cu+Ni 3 layer coating, the best available. <span class="a-text-bold">Tolerance:</span>The tolerances of all the dimensions are +/-0.002in with coating. All magnets may chip and shatter, but if used correctlycan last a lifetime. Keep away from pacemakers. Not for children, parental supervision required. If damaged please dispose of completely. Shards are still magnetized and if swallowed can inflict serious damage if mag Magnets Each Of These Bar Magnets Provides 90 Pounds Of Holding Power Maximum Working Temperature 176 F (80 C) Material: Sintered Ndfeb Neodymium Rating: 14,400 Gauss Pulling Force Pole Orientation: Axially Magnetized, The Poles Are On The 1/2&#034; Thickness Coating: ni+Cu+Ni 3 Layer Plated Tolerance: All The Dimensions Are +/-0.002in With Coating