These Avery weatherproof parcel labels are made from extremely durable polyester, which is oil, dirt and UV resistant, as well as waterproof, tear proof and temperature resistant from -20 to 80 degrees Celsius. For use with laser printers, these labels are ideal for use with a variety of packing materials, including polythene envelopes. Each white label measures 99.1 x 139mm. This pack contains 25 A4 sheets, with 4 labels per sheet (100 labels in total).