The product itself is great. As others said, no instruction manual is included, but it's pretty standard if you've ever put a screen protector on something before. Take off the side labeled (1), apply that side to the screen, then take off the side labeled (2). It fits my Nintendo DS Lite screens perfectly... Almost too perfectly. I'm not entirely sure how I'm going to get these off if I ever need to replace them. The screen protector certainly took its time getting to me though -- it took over a week to reach me (I've been spoiled by Prime 2-day shipping).