Choose the most secure labels that won't peel or curl with Avery shipping labels using Ultrahold permanent adhesive. Avery Ultrahold adhesive sticks and stays, unlike basic labels, and applies securely to a wide range of surfaces including envelopes, cardboard, paper, plastic, glass, tin and metal. Created with TrueBlock material, each label completely blocks out any text or colors underneath the label to make sure that your print is as clear as possible. These labels are also resistant to damage from chemicals, scuffing, tearing, smudging and up to one year of outdoor UV light. Avery labels are heat and cold resistant, acceptable for food contact and can reach grade A barcode readability.