Frames are made of common metal alloy, high nickel alloy metal frame, lightweight titanium or titanium alloy metal frame, injection molded plastics, sheet plastic, carbon and metal-plastic hybrid. These frames have different characteristics of different materials:
Common metal frame new, cheap;
High nickel alloy metal frames with high elastic, but some people are more prone to allergies;
Titanium and carbon materials are light but expensive; plastic cheap and fresh color; plate warp but is more expensive.