Made of 100% food-grade silicone, <br><br>High heat resistance which up to 260 degree centigrade <br>Silicone is an incredibly versatile material. Silicone generally refers to a family of materials <br>that are based on polymer chains with alternate silicon and oxygen atoms. <br>Silicon-oxygen linkages are found in other high temperature materials such as quartz, <br>glass, and sand. This accounts for silicone’s superior heat resistance when compared to other elastomers. <br><br>soft and flexible, inside diameter 5mm, outside diameter 7mm