Fits well on the 2018 Mazda CX-5. Of course, this is a bit noticeable compared to other nuts, but it serves its purpose perfectly. I see no problem with the key. I was a little wary of buying it, but to get it for 1/3 the price of the manufacturer's branded version, that's a pocket saver at work. I don't see wheel stealing in my area, but it only takes one copy for someone to ruin your life. It's better to pay $20 for sanity than $500 for insanity, even if just one bike gets stolen.