Brilliant customer service and product! I ordered a blue light blocking screen for an Apple MacBook as a birthday gift for someone. They had measured the width of their screen side to side, rather than from corner to corner, thus I ordered the wrong size! On discovering that I’m the screen was too small, I emailed Ocushield to arrange an exchange. Despite the fact that this was my error and not theirs, they promptly sent me the correct size out with no expectation that the other be returned! The screen itself attaches beautifully, and can be removed with ease if needed. Definitely makes a huge difference to eye strain, worth every penny!