Brady Labels - B-490 (Sold as 2-Pack)Durable Polyester (B 490) markers are designed for use in laboratory identification applications such as vials, centrifuge, tubes, test tubes, straws and slides. B 490 labels can be applied to frozen surfaces including glass and polypropylene stored in liquid nitrogen when wrapped around itself by at least 1 8" White polyester material has a permanent acrylic adhesive and is thermal transfer printable Good print smudge resistance, solvent resistance