Puffco products that have a glass coating has been designed with your complete safety in mind. The coating was tested and complies with the required limits of ISO 10993-5:2009 for In Vitro Cytotoxicity and ISO 10993-10:2010 for Irritation and Skin Sensitization. These are the FDA-recommended tests for a medical device with limited contact duration with intact skin or mucosal membranes (surface device).