Titanium frame
A frame made of titanium, a light, strong metal that does not rust and rarely irritates skin.
Also: titanium
Titanium is about 40 percent lighter than steel for the same strength and resists corrosion and sweat. It is hard to weld and shape, and makers in Sabae, Japan, were among the first to produce titanium frames, in the early 1980s. Titanium suits thin rimless and semi-rimless styles. Beta-titanium, an alloy, is springier and is used for flexible arms. Titanium frames can be coloured by anodising or plating.