Red Cast Alnico 5 Bridge Magnet With Keeper, 1.18" Wide, 0.78" High, 0.78" Thick, 0.20" Hole On Top (Pack of 1)
13 pounds of pull perpendicular to a flat, ideal holding surface.  This pounds of pull does not apply to shear force.  Pounds of pull are increased by using a holding surface with the highest iron content possible.  Also the thicker the steel holding surface the higher the pounds of pull.  Layers of paint and other finishes decrease the pounds of pull.