Chastity device discussions and reviews discussion

Hello. I shared this over on another board earlier, but I’m hoping for different perspectives. I’m purchasing my first chastity device and this one caught my attention:

The price is reasonable, it provides complete coverage, and includes a vented tip which is what I want. (I don’t know all the technical terms). The only issue is that the ring fits just a bit snugly for my guys. A review on another site mentions “the inner circumference is about 4 3/4 inches.” I used a measuring tape to wrap around the base of my penis, up where the scrotum meets the groin area. (Hard for me to describe clearly, but roughly where the ring sits), and it measures exactly 4 3/4 inches, though slightly tight. I messaged the manufacturer to ask if they offer other sizes, but if not, is there a way to make it just a little looser using pliers or similar tools? Since it’s all metal, it should be able to stretch without breaking. We’re only talking about millimeters here. I really can’t spend any more money right now. I’m ordering from another retailer because no Amazon sellers ship to Canada, and this is the sole option under $50 that isn’t on . Also, since I have a bit of extra weight, will my ring size shrink as I lose fat (specifically pubic fat)? Does anyone know exercises that target that area? I can provide more info if needed. Thanks.

Would this method work? Since I've never used a chastity device before, I'm not sure if there are any threaded components that might get damaged during the process. Another thing to consider is how sturdy the metal is and whether it can be cut.