For starters, this is 25mm outside diameter including the protective coating on the cable. This is not the diameter of the steel braid. I did not expect that to be the case, since it is obvious from the pictures, price and weight. I agree with another reviewer that it is difficult to know the diameter of the steel braid because of the lensing effect, but I did compare it to my Brinks 5/8 inch steel braid cable and this seems to be the same diameter. I did not cut mine open to verify, but I would bet money its at least 1/2 inch steel braid in there. I needed this for my boat trailer spare tire. It is only barely long enough to encompass my tire, the stand off due to the carrier, and the trailer frame I-beam, but it does make it with a couple inches to spare. I have one of those very common rim designs that have 1.5 inch holes. This fits right through no problem using the hook end (i.e., not the lock end). The lock feels flimsy and plastic, but does work. I have no trouble locking and unlocking mine, however, the mechanism is unique and maybe not what people are used to. Best use would be for something that is more of a lock it and forget it. Daily lock/unlock might get a little annoying with this mechanism, but I would have no problem with it. The key has a little LED light on it that lights up when you push it into the lock. For my use, the extra protective covering is welcome. This will occasionally touch salt water (I expect only the cable part), and more covering is likely better for corrosion. It does add weight, though. So, again, this is more of a lock it and forget it cable. Overall, its a bit heavy for daily handling. None of these cables will give you great security. This is just a deterrent. I got to say, though, on looks alone I would move on if I was a thief looking for a quick score. This cable is intimidating. Does it make my item theft proof? Nope, not at all. However, they will need some determination and proper tools. A simple pair of cutting pliers or a small crowbar isnt going to do it. If you are needing maximum security for a high dollar item, get something else. If you just want the illusion of security and/or the item really isnt that valuable, this will be fine. Overall, I am very happy with this purchase. The item is exactly what I was looking for in a boat trailer spare tire locking cable and at a fair price. I would buy this again.