Wilmad's PTFE coated NMR tube has excellent mechanical strength that can survive a 6 foot free drop at any angle. The PTFE coating also yields zero background in proton spectrum. These two features make it ideal in food and pharmaceutical studies where glass coating is a must to protect the sample. PTFE coating carries max working temperatures up to 180 ℃ (360 °F) and its smooth surface makes it food safe and very easy to wash. The inner diameter is precision bored with 8 micron tolerance which guarantees a sample height reproducibility within 1% at a given sample volume.