Graphite ferrules for Shimadzu have an upper temperature limit of 450 deg. C. They are made from high purity graphite. Designed for Shimadzu capillary GC use. Graphite is soft and can be re-positioned on the capillary, if not over-tightened. All the ferrules come in packages of 10. Packaged: 3 in. x 3 in. x 1/4 in. Plastic Dial Pack; Weight: 7.3 g