Superior PBT Material For a textured finish and enhanced durability: Made of high-grade thermoplastic with a sturdy, textured finish that never wears out, the keycaps are crafted with extra-thick walls fit for intensive gaming that produce satisfying, solid keystrokes. Doubleshot Molding with Ultra-thin Font The thinnest font ever on a PBT keycap: Our unique doubleshot precision molding process produces the thinnest font ever seen on a PBT keycap that is also backlight compatible and fade-resistant despite intense usage. Fit most mechanical and optical keyboards For out-of-box compatibility: Consisting of 120 keycaps and additional stabilizers for optical and mechanical keyboards, the Razer PBT Keycap Upgrade Set fits both Razer and standard 104/105 key US and UK layouts. PBT Material An Ultra-Durable, Shine-Resistant Plastic: PBT (Polybutylene terephthalate) is a thermoplastic that is known to be stiffer and more durable than other plastics commonly used in keycaps like ABS. It retains its color and texture and will not develop a glossy finish nor fade over time.