0.402" id

This neodymium countersunk magnet is made of super strong N42 NdFeB (NIB) material, coated with Plastic. The dimension of this Medium neodymium magnet is 1 1/4″ od x 0.221″ id x 0.402″ id x 3/8″ thick w/ hole to accept #10 screws, magnetized Through Thickness. Its individual pull force is approximately 20.49lbs.