Kryptonite Transit FlexFrame-U Bracket Bike Lock Mount, Lightweight Mounting Bracket for Kryptonite U-Locks 13mm-16mm Shackles, Bicycle Attachment Accessory,Black

I have a Kryptonite lock on one of my bikes, and decided to swap it between my city bikes and my gravel bike. This made it simple. Each bike has a different mounting angle, so having the extra connector was a big plus. I was able to mount a connector on each side of the U.

This is a really great mount, it can fit onto a normal round tube bike or it can also fit onto a square or rectangle shaped tube like on some of the newer bikes. I bought 2 of these and mounted one on my bike and the other on my wife's bike, so the lock can switch from bike to bike. There are some reviews that say this is a bad piece of equipment because it does hold properly or some other reasons and I can tell you this mount will mount on your bike very securely and easily, but there is a right way to do it and a wrong way. Make sure the strap is wrapped around the tube securely and snugly before you tighten the screw that holds it in place and it will be in place and won't move at all when done. Another thing to note about this is that when your lock is placed into this mount it is held onto the bike securely and won't come off, but the lock can still move back and forth. The silver piece on the lock that slides into the mount and locks in place holds the lock to the mount but it just slips over the round bar of the lock and can spin in place, which means when locked in it can still back and forth. I use a small velcro strap to hold the round bar side of the lock w/o the silver piece to the frame or where you decide to place it. (I know this sounds confusing, but you will know what I mean when you get it). It is a good mount and I completely recommend it to everyone. (the picture of the lock mounted into the downtube bottle mounts looks great, but the lock will not stay in that upright position, it will fall to either side and hang down unless you hold it in place with a strap around the lock and downtube)

This lock is a tragedy, the hubris of a successful lock company, a fleecing of its consumers (It's a cliche story, I know.) When I originally bought the lock, this bracket technology was included, so I mounted it to my seat tube assuming that it would work....It did not. It stayed in place maybe a few weeks before sliding down toward the petals, towards Hades. Then, I tried it in multiple other places, and it also remained where mounted for just short periods. I gave up, cursed the gods, and I tossed it.A couple years later, tired of the weight of it in my bag or the rattle of it on my cargo rack held in place by a bungee cord, I decided to buy another bracket, thinking that maybe the first one I had was defective. Clearly, only my lack of foresight was, similar to whoever made this lock, perhaps the lowly people of the Iron Age. The replacement bracket seems even worse, if that is possible, devised by . The final and most recent failure for me was when the blinking thing actually stopped me from moving, as the lock swung back in forth, clashing like Sympleglades against my shins interrupting my pedaling. I threw the lock in my bag and the bracket in the trash, which of course, slid right down to the bottom, likely out of habit or perhaps because that is where it belonged (Poor lock mount like Oedipus, The Fates were against you.)I hate having to put the lock in my myriad of other storage spots, but I've conceded defeat to this Herculean task. I've also decided that I likely won't buy another Kryptonite lock because I don't really have faith in a company that cannot design a simple mounting bracket. Presumably, a sound lock is more difficult to create than a mount for said lock but...? Their designer/engineer should have his liver pecked at every day like Prometheus (Okay, maybe not that bad but note to engineer--you don't have Impostor Syndrome; you're really don't belong there. Consider yourself more of a hobbyist than anything else) In the words of Comic Book Guy, "Worst Mounting Bracket, ever."

A little complicated to install, but does as described. It may take a little extra time if you have other accessories such as water bottle and/or air pump attached to your bike already, but you should be able to find a space.

I bought this bracket setup since the original would not fit on today's larger frame tubes. This bracket is pretty versatile due to its universal mounting system which allows it to be mounted in several locations on the frame.Seat stem, top tube, down tube, are all reasonable spots to consider depending on your riding position and bike frame compatibility. I chose the seat stem just below the top tube. The mount itself is easy to install with the padded strap/buckle and the allen 4mm hex nut which attaches the swivel/rotating locking mechanism. I rotated mine enough so the u-lock would angle in the same orientation as the seat stays. The system comes with two different sized collars that lock into the mount. They both fit my larger u-lock. With the smaller collar you would have to trim off the rubberized plastic protecting cover where the larger one fits over the top of the protective covering but it does move around a bit even when really tight. I rotated mine just enough to tuck the top under the seat so my leg would not brush against it. I would recommend if you really like the mounting position to use some loctite blue on the hex nut for the mount and on the set screw on the locking collar so they don't come loose which is what I did. The kit also comes with a hex wrench, however I used a longer one for a bit more leverage. Just for interest I would like to see images of the failed attempts to install this on a bike to try to determine why. Overall very nice and it works well and as intended. As far as durability I am not sure but in 6 months I will post something if I change my opinion.