The blue refillable Staedtler Lumocolor 351 whiteboard marker is suitable for whiteboards and glass and porcelain surfaces. The whiteboard marker has a writing width of 2mm. The markers dry quickly and are virtually odourless. You can easily remove the ink with a whiteboard eraser. The markers are equipped with DRY SAFE technology. This allows you to leave the markers uncapped for days without them drying out.