This keycap is made of Aluminum Alloy and silicone with ultrasonic bonding. Fit on Row 4 which includes the Esc, F1-F12, 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.
* Due to the light and screen difference, the item's color may be slightly different from the pictures.