Detachable 2-way privacy filter for the Microsoft Surface Go Blocks the view from two sides (left and right) Narrows the field of vision on the screen to +/- 30 degrees Blue light reduction: Filters out the harmful rays by up to 48%, easing eye strain and aiding natural sleep patterns Touch screen compatible with anti-fingerprint coating: Up to 3H hardness, makes fingerprints on the filter surface invisible. Anti-glare coating: Reduces glare from any outside light sources