20mm x 5mm x Hole 5mm Neodymium Countersunk Magnet – N52 Grade 

Key Features:

• Dimensions: 20mm Outer Diameter × 5mm Thickness × 5mm Inner Hole Diameter
• Countersink Profile: Accommodates standard #6, #8, or M5 flathead wood/machine screws for flush mounting
• Precision Tolerance: ±0.05mm 
• Magnet Grade: N52 
• Pull Force: Approx. 20.3 lbs 
• Coating: Nickel-Copper-Nickel (Ni-Cu-Ni) triple-layer plating
• Magnetization: Axially magnetized (Poles on the flat circular faces, countersunk on the North or South face)

Material Description:

Our 20mm x 5mm countersunk N52 ring magnets provide an exceptionally strong, mechanically anchored fastening solution for demanding industrial, architectural, and millwork projects. The 5mm depth provides substantial magnetic volume, allowing the deep field to project through non-magnetic finishes or small air gaps. Featuring an integrated 5mm countersunk hole, it accommodates heavier-duty M5 or flathead screws. Because the screw head drops perfectly flush within the recessed pocket, it permits uninterrupted metal-to-magnet surface contact, maximizing the available 19.5 lbs of holding force.

Handling Advice: DANGER: Industrial countersunk ring profiles require careful, controlled installation. Neodymium is inherently brittle like ceramic. Over-tightening installation screws with power tools can cause the magnet to split or crack at its recessed center point—always hand-tighten with care. These magnets also possess immense snap velocity; never let them free-fly together or snap onto steel tools, as they will shatter upon impact.

Warnings and Safety Information:

• Crush Hazard: High risk of serious skin and finger pinches or blood blisters. Handle with industrial focus.
• Fragility Hazard: Do not over-tighten screws. High impact from snapping together WILL fracture the ring wall.
• CHOKING HAZARD: Keep securely stored and out of reach of children and pets.
• Medical Safety: KEEP AWAY from pacemakers and sensitive medical implants at all times.

Applications:

• Heavy-duty hidden closures for heavy security doors, secret panels, and commercial custom cabinetry
• Mechanical anchoring for large removable wall partitions, acoustic panels, and ceiling graphics
• High-vibration shop-tool organization, heavy-duty jigs, fixtures, and custom workbench hold-downs
• Secure, screw-in fasteners for modular retail displays, heavy signage, and exhibition presentation frames
• Heavy-duty 3D-printed equipment enclosures and removable machine guarding plates