The keyboard protects that I received is very flexible, light, thin and very transparent, as I wished. It fits PERFECTLY my QWERTY keyboard (MacBook Pro 13-inch), covers and adheres to all keys. In addition, the surface of the silicone is soft and does not interfere at all using the keyboard.
In short, it's the cheapest product I've found suitable for QWERTY keyboard (not QWERTY) while he fills all my expectations.