60% Vespel / 40% Graphite ferrules have an upper temperature limit of 400 deg. C. Ferrule has no through hole; can be used as a plug or drill to size for your special application. (Molding indentation is visible in photo.) One piece design requires no back ferrule. Packaged: 2-3/8 in. x 1-1/4 in. x 1/2 in. Plastic Hinged Box; Weight: 8.5 g.