Magnetic portable knife sharpener uses standard diamond abrasive plates measuring 150mm x 20mm x 1mm. 

The sharpener uses 10mm x 3mm neodymium magnets. The magnets are held in place by a tight fit; you can apply a dab of super glue if desired. 

To ensure the two halves of the pins hold together more securely, it's best to use glue during assembly.