Ceramic VIII ferrite block magnet measuring 20 × 8 × 3 mm. Listed pull force: 0.93 lb (0.42 kg). Compact rectangular magnet for assembly evaluation. SKU 8643.
SKU 8643 is a Ceramic VIII ferrite block magnet measuring 20 × 8 × 3 mm. Its compact rectangular shape can be considered for fixtures, holding arrangements and production assemblies where ferrite material and a thin block geometry meet the design requirements.
| Size | 20 × 8 × 3 mm |
| Grade | Ceramic VIII ferrite |
| Br | 4,080 Gauss |
| Listed surface field | 1,844.02 Gauss |
| Listed pull force | 0.93 lb (0.42 kg) |
| Tolerance | ±0.004 inch |
| Listed maximum temperature | 350°C |
Check the drawing and dimensional tolerance against the intended mounting pocket. Provide clearance and support the brittle ceramic block in its housing. Avoid impact, bending or an interference fit that could chip an edge or crack the magnet.
The listed 0.93 lb pull is a comparison value rather than a safe working load. Target steel thickness, contact area, surface condition, air gaps and loading direction affect actual retention. Test the completed assembly under its intended conditions before committing to production quantities.
The listed maximum temperature is a product reference; validate magnetic performance at the intended operating temperature and check any adhesive or housing against its own limits. Include working gap, target material and temperature in your application requirements.
Compare material choices in our ferrite versus neodymium guide, browse ceramic and ferrite magnets, and explore geometry with the pull-force calculator. Send drawings and quantities through the Magnet RFQ Builder for application-specific sourcing.

| Length | 20mm |
|---|---|
| Width | 8mm |
| Thickness | 3mm |
| Pull Force | Less than 1lb |
| Shape | Block / Bar |
18105 in stock
| Title | Quantity | Price Per Magnet |
|---|---|---|
| Quantity Discounts | 1 - 9 | 0% $1.60 |
| Quantity Discounts | 10 - 49 | 6.15% $1.50 |
| Quantity Discounts | 50 - 99 | 10% $1.44 |
| Quantity Discounts | 100 - 999 | 15% $1.36 |
| Quantity Discounts | 1000 - 4999 | 30% $1.12 |
| Quantity Discounts | 5000 - 9999 | 40% $0.96 |
| Quantity Discounts | 10000 + | 50% $0.80 |
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