Large Ceramic Donut or Ring Magnet Size: 4.00 inch outer diameter, 2.33 inch inner diameter, 0.50 inch thick Material: Ceramic (ferrite) Why this magnet is useful Ring shape provides a clear center opening for shafts, bolts, or mounting hardware, making installation simple and secure. Ceramic material offers reliable magnetic performance for general purpose applications where strong rare earth magnets are not required. Durable and stable magnetic properties make this magnet suitable for repeated use in assemblies and fixtures. Key features and benefits Exact dimensions for predictable fit: 4.00 inch OD, 2.33 inch ID, 0.50 inch thickness. Flat faces and uniform thickness allow straightforward mounting and even contact with mating surfaces. Stackable to increase magnetic force when needed. Lowcost, maintenance solution for many mechanical, educational, and craft projects. Handle with care: ceramic magnets are brittle and can chip if struck or dropped. Practical applications Speaker and audio projects: use as the field magnet in custom or replacement speaker assemblies where a ring magnet is required. Motor and generator prototypes: central opening accepts shafts or fasteners up to 2.33 inches in diameter, useful for DIY rotors or magnetic couplings. Workshop fixtures and holding devices: secure lightweight components, jigs, or templates for fabrication and assembly tasks. Specifications Shape: Donut or ring magnet Material: Ceramic (ferrite) Outer diameter: 4.00 inches Inner diameter: 2.33 inches Thickness: 0.50 inch Notes for use Ceramic magnets are brittle; avoid impact and use protective padding during installation. If higher magnetic strength is required, consider stacking multiple units or choosing a different magnet material.