When you think of the screen protectors of old, you're probably thinking of TPU. TPU screen protector is a flexible plastic that's a huge hassle to install (it involves using a spray solution and squeegeeing out lots of bubbles), doesn't feel very smooth (thanks to its almost rubbery texture), and adds an "orange peel" type glare to your phone's screen. Still, it's flexible, so it can go edge-to-edge on any phone, it has better impact protection than PET, and it has limited "self-healing" powers for small scratches. http://www.yccscreenfilter.com/tpu-screen-protector/