Durable 3mm thick acrylic is reusable and long-lasting.

Write on the smooth surface (but not on a frosted side) with a fine-tip permanent marker and wipe clean with rubbing alcohol when finished.

5.5 cm tall x 4 cm wide x .3cm thick

Neodymium magnet is nickel plated and is not a toy. Keep out of reach of children and away from magnetic media such as credit cards and electronics.