Titanium has the highest strength to weight ratio of any metal, and the alloy used on this spike...Titanium alloy 6Sl-4v... is stronger than mild steel, non-magnetic and extremely resistant to corrosion.  It is the same alloy commonly used to fabricate artificial hips and other joints.

This spike is made from solid bar stock, has a threaded removable head and an o-ring seal to keep its contents waterproof.  These spikes and similar devices are used by spies and subversives to hide, transfer and retrieve notes, cash and small items.  Its shape allows it to be pounded into the ground for a later retrieval, and it has a rawhide thong attached.  It has a natural matte unpainted finish, and its dimensions are 3/4" in diameter by approx. 6" in length.