Old Stone Tags (for outdoor use) are made out of PVC and are resistant to weather, chemicals, corrosion, shock, and abrasion. PVC is the preferred choice for many different long-life and outdoor products. The NFX NTAG213/215 inlay within the tag is among the most durable and reliable on the market. Follow this link for full specifications. The tag is coated with a protective UV layer guaranteed for 20 years in direct sunlight 24/7. The tag will function properly, as intended, in temperatures between -40 and 200 degrees Fahrenheit.