Both Surface 3 and Pro 3 Type Covers have a loop to house the Surface Pen. When the Surface 3 was announced, a smaller version, the Surface 3 Type Cover was released. The Surface Pro 3 Type Cover has a touchpad with glass beads replacing the felt-like material used in previous generations. The Surface Pro 3 Type Cover features a second magnetized strip that can be rested against the screen to prop the keyboard up at an angle. With the release of the Surface Pro 3, a newer cover called the Surface Pro 3 Type Cover was released to fit the bigger screen.
The Type Cover 2 is thinner and features back-lit keys. It was upgraded along with the second generation Surfaces to the Type Cover 2 which substituted the plastic material for the felt-like material found on the Type Covers. With the release of the first generation Surface Pro, Microsoft launched the Type Cover which has tactile keys. Microsoft never made another Touch Cover after the release of the Surface Pro 3. In addition, the Touch Cover 2 also supported key gestures and was backwards compatible with the first generation Surface devices. With the release of the Surface 2 a Touch Cover 2 was announced which increased the number of sensors to 1,092 and added backlit keys while being thinner than the original Touch Cover. The original touch cover came with 80 touch sensors and was pressure sensitive.
