PVC for Nalgene® PETG Media Bottles. These bands provide a tamper-resistant seal to ensure the integrity of the bottle contents. Simply apply the recommended application torque for Nalgene® closures, and slide the heat-shrink band over the closure and bottle neck; heat the band to shrink and secure contents. Bands are gamma stable and include a perforated ''tear strip'' feature for easy removal. They are available in 4 sizes to mate with Nalgene® PETG square media bottles. PVC for Nalgene® PETG Media Bottles. These bands provide a tamper-resistant seal to ensure the integrity of the bottle contents. Simply apply the recommended application torque for Nalgene® closures, and slide the heat-shrink band over the closure and bottle neck; heat the band to shrink and secure contents. Bands are gamma stable and include a perforated ''tear strip'' feature for easy removal. They are available in 4 sizes to mate with Nalgene® PETG square media bottles.