From the Manufacturer

This tungsten carbide tip scriber marks stainless steel, copper, ceramics and glass. It has a screw chuck for reversing tungsten carbide point when not in use. Measures 6" overall.
The and Instruments 88 Tungsten Carbide Scriber is a great choice for both machinists and hobbyists.
This engraving pen comes with a chuck for reversing tungsten carbide point when not in use; this scribe is an essential machining tool
The durable etching point works effortlessly on hardened and stainless steel, ceramics and glass
The scriber point is also easily replaceable, providing like-new performance for years
the convenient pocket clip and reversible point make this scriber an ideal travel companion for those on the go