This keycap is doubleshot molded (one of the highest quality mold possible) and is made of Polycarbonate (PC) plastic. This combination produces one of the highest quality keycaps, with its legends being resistant to scratching and even sandpapering. Fit on bottom row 1.25u which includes the CTRL, Windows, ALT, etc (check the keycap size chart); and compatible for Cherry MX / Gateron / Kailh / Razer / others MX clone mechanical switch. Designed for backlit mechanical keyboard especially, but you can put on non-backlit keyboard too.