Holey PowerMag, 9/16" x 1/8" thick with 3.5 lbs Holding Power. Powermag with countersunk hole in middle & screws to attach to surface, 10/pack Holey PowerMag, 9/16" x 1/8" thick with 3.5 lbs Holding Power. Powermag with countersunk hole in middle & screws to attach to surface, 10/pack