• Dimensions: 3/8" od x 1/8" thick with countersunk hole for #4 screw
• Tolerances: ±0.004" x ±0.004" x ±0.004" x ±0.004"
• Material: NdFeB, Grade N52
• Plating/Coating: Ni-Cu-Ni (Nickel)
• Magnetization Direction: Axial (Poles on Flat Ends)
• Weight: 0.0532 oz. (1.51 g)
• Pull Force, Case 1: 4.27 lbs
• Pull Force, Case 2: 8.30 lbs
• Max Operating Temp: 176ºF (80ºC)
• Brmax: 14,800 Gauss
• BHmax: 52 MGOe

Strong countersunk ring magnets sized specifically for #4 flat-head screws.  The south pole is on the side of the magnet with the large hole, where the head of the screw would be.

These countersunk rings can be used for a wide range of applications including closures for cabinet doors and handbags.