The abbreviation for Titanium is Ti. The Ti-tack is a very sharp tip for very precise pushing or to push through the nasty sound deadening that is being sprayed on roofs. The Ti-tacks have a lock hole at the base so you can put a smaller tool through it and tighten it down so it will not come loose. The Ti-tack  weighs .17oz/ 5gr. The anodizing on Titanium will change colors with body oils and is only a couple microns thick. It will wear off over time, or with rough treatment.