Mr-Label Self-adhesive Labels - Weatherproof | Tear Resistant | Durable - Ideal for Small Producers and Scavenger Hunt Game Players (10 A4 Sheets, 10 Labels, White) They are waterproof, tear-resistant, oil-proof, flexible and self-adhesive. Unlike the traditional label which may fade or be damaged easily, they stay stuck and holding fast in outdoor use. A must for making scavenger hunt game like Munzee, combined with a laser printer, they will save time and you just need to print and deploy. These distinct labels are tough, creating a quality and professional look, ideal solution to market and label products and mark metal parts. It is a great innovation for small producers of toiletries, foods, crafts etc. Because of these labels are made of special material, they need a Laser Printer to work properly. But you can still handwritten with a permanent marker.