N40 neodymium ring magnet measuring 6 mm OD × 4 mm ID × 5 mm thick, axially magnetized with Ni-Cu-Ni coating and a listed 3.97 lb pull force. SKU 9209.
SKU 9209 is an N40 neodymium ring magnet measuring 6 mm OD × 4 mm ID × 5 mm thick. Its compact annular geometry gives engineers, OEMs, and procurement teams a small stock ring for sensing, alignment, shaft or pin clearance, fixtures, prototypes, and embedded assemblies.
| Outer Diameter | 6 mm |
|---|---|
| Inner Diameter | 4 mm |
| Thickness | 5 mm |
| Tolerance | ±0.004 in |
| Material | NdFeB |
| Grade | N40 |
| Coating | Ni-Cu-Ni |
| Magnetization | Axial, through thickness |
| Listed Remanence (Br) | 12,850 gauss |
| Listed Maximum Energy Product | 40 MGOe |
| Listed Pull Force | 3.97 lb |
| Approximate Weight | 0.0208 oz |
| Listed Maximum Temperature | 80°C / 176°F |
This part is axially magnetized, so the north and south poles are on the two flat annular faces. It is not a true radially magnetized ring. The 4 mm center bore can provide clearance for a shaft, pin, fastener, or other assembly feature, subject to the mechanical tolerances of the application.
The listed pull value is a reference measurement under defined conditions. Air gap, target steel, contact geometry, temperature, surface finish, and the percentage of annular face actually contacting the target all affect real-world performance. Review What Is a True Radial Magnet? when comparing axial and radial ring designs.
Browse stocked ring magnets for related sizes, compare material options with the Neodymium Magnet Grades Chart, or use the Magnet RFQ Builder for custom OD, ID, thickness, coating, tolerance, magnetization, or production quantities.

| Weight | 0.001299 lbs |
|---|---|
| Dimensions | 0.236220 × 0.236220 × 0.196850 in |
| Diameter | 6mm |
| Inner Diameter | 4mm |
| Thickness | 5mm |
| Strength / Grade | N40 |
| Pull Force | 1-5lbs |
| Magnetization Direction | Axial |
| Shape | Ring |
| Surface | Coating | Thickness(microns) | Color | Resistance |
|---|---|---|---|---|
| Passivation | 1 | Silver Grey | Temporary Protection | |
| Nickel | Ni Ni Ni Cu Ni |
10-20 | Bright Silver | Excellent Against Humidity |
| Zinc | Zn Cu Zn |
8-20 | Bright Blue Shinny Color |
Good Against Salt Spray Excellent against Salt Spray |
| Tin | Ni Cu Sn | 15-20 | Silver | Superior Against Humidity |
| Gold | Ni Cu Au | 10-20 | Gold | Superior Against Humidity |
| Copper | Ni Cu | 10-20 | Gold | Temporary Protection |
| Epoxy | Epoxy Ni Cu Epoxy Zn Epoxy |
15-25 | Black, Red, Grey |
Excellent Against Humidity & Salt Spray |
| Chemical | Ni | 10-20 | Silver grey | Excellent Against Humidity |
29 in stock
| Title | Quantity | Price Per Magnet |
|---|---|---|
| Quantity Discounts | 1 - 9 | 0% $3.00 |
| Quantity Discounts | 10 - 49 | 6.15% $2.82 |
| Quantity Discounts | 50 - 99 | 10% $2.70 |
| Quantity Discounts | 100 - 999 | 15% $2.55 |
| Quantity Discounts | 1000 - 4999 | 30% $2.10 |
| Quantity Discounts | 5000 - 9999 | 40% $1.80 |
| Quantity Discounts | 10000 + | 50% $1.50 |
Custom magnets and magnetic assemblies, factory-direct. PPAP and ISO 9001 documentation available.
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