Uni Chalk Marker Pen PWE-5M: chalk-based markers for signwriting on non-porous surfaces, easily removed from such surfaces with a damp cloth. 5mm bullet tip is perfect for writing and smaller details. Ideal for signs in pubs, cafes and restaurants. Rain-resistant, so they're great for signs outdoors, but can be removed from non-porous surfaces with a damp cloth or mild detergent. Uni-Ball PWE-5M Chalk Marker 4 Chalk Markers in a Handy Wallet Bullet Tip 1.8mm-2.5mm Line Width For Use on Porous and Non-Porous Chalk Boards Black Boards - Glass & Plastic Produces a Vivid Opaque Vibrant Colour Finish Bullet Tip Special Formulated Ink for Easy Wipe Clean Line Width: 1.8 to 2.5mm Odour Free - No Solvents & No Alcohol