This Saphierlinse has a diameter of about 9.5mm and fits into the recess of the HTC One M7. This has a diameter of about 11mm. The glass is a bit small, but that's still no problem. The bearing surface of the glass is large enough to fix it reliably with a Felxiblen-Gelkleber. In addition, the glass is thin enough so that it does not project after assembly. It's even a bit thinner than the original plastic cover of the camera.
Installation I have done according to the enclosed instructions. This was very easy to perform, because the smart phone this must not be dismantled. The old plastic lens can be easily removed from the outside and installed the new one.
After installing the camera is finally again reliably protected from the ingress of dust and moisture. Also see the pictures again from super, the sharpness of these images has improved considerably again with this sapphire lens. (Since I have the original Broken glass away for protection and had pasted over with a Tesa, was the quality of the images just mediocre).
My conclusion: very recommendable also for the HTC One M7.