CMS Magnetics Strong Neodymium Bar Magnets N45 2 Pieces 3 x 1/2 x 1/4&rdquo; w/ 2#6 Counter Sunk Holes Powerful Permanent Magnets: Strong Holding Power, Grade N45  31 lb Per Magnet with Direct Touch and Direct Pull, 13,500 Internal Gauss; Great Strength for its Size Numerous Applications: Useful Magnets for Holding, Mounting, Home Improvement, DIY Projects, and Many More. Great as a Cabinet or Shower Door Catcher 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 Easy Installation: Countersunk Holes Designed for #6 sized screw for Easy Installation