I used to have a similar ring attached to my Samsung S7 Edge and had truly liked how I could carry my phone by slipping the ring through my finder, hang it on a hook I have installed in my truck and not have to worry about it falling through, or being stolen from, the shopping cart while in the store (simply twist the ring vertically, slide between the bars on the cart and then twist the ring to horizontal).
This product has great adhesive and you should have no worries of it falling off after you have attached it to your phone! I recommend.