The boffins at GoPro weren't thinking about people strapping their camera without its protective case on to the front of miniquads and slamming them at speed into all manner of hard stuff. Because of that, the lens is pretty exposed. That's where our slip-on lens protectors come in.
These are intended to take the brunt of any impact and break instead of your lens and every scratch they absorb is one less on your actual lens.
We keep a couple in our flight bags at all times and use them in conjunction with an ExoPro camera bumper for even better protection of our poor, abused GoPros.
GoPro not included (Duh!)