4mm x 8mm (5/32" x 5/16") Diametric Neodymium Cylinder – N52 Grade 

Key Features:

• Dimensions: 4mm diameter × 8mm thickness (Approx. 5/32" × 5/16")
• Pull Force: Approx. 3.13 lb
• Magnet Grade: N52 
• Magnetization: Diametrically Magnetized (Poles on the curved sides)
• Coating: Nickel-Copper-Nickel (Ni-Cu-Ni) triple-layer plating for corrosion resistance
• Shape: Cylinder / Rod

Material Description:

Our 4x8mm Diametric N52 magnets are the gold standard for rotary encoders and Hall-effect sensors. Unlike standard axial magnets, the magnetic field radiates from the sides of the cylinder, allowing the sensor to detect the exact angular position as the magnet rotates on its axis. The 8mm length provides a larger "target" area for sensors compared to shorter discs.

Important Note: Diametric magnets align side-to-side. They will not stack end-to-end like traditional magnets. Neodymium is brittle; at this 8mm length, avoid side-impact or dropping them on hard surfaces to prevent snapping or cracking.

Warnings and Safety Information:

• Choking Hazard: Small rod size is dangerous if swallowed. Keep strictly away from children and pets.
• Unusual Attraction: These magnets will roll toward each other to align poles. Use non-magnetic tools for installation.
• Medical Safety: Keep away from pacemakers and sensitive medical electronics.
• Storage: Store in a non-ferrous container to prevent accidental attraction to steel tools or surfaces.

Applications:

• High-precision rotary encoders and angular position sensors
• Magnetic stirrers for small-volume laboratory mixing
• Precision DC motor and generator prototyping
• Magnetic "rollers" for small-scale mechanical assemblies
• Scientific demonstrations of transverse magnetic field lines