KryptoniteEvolution Long Shackle Bike U-Lock, Anti-Theft Security, 14mm Steel Shackle with Mounting Bracket and Keys, High Security for Bicycles Scooters,Black

Heavy, but does the job. I use 2 locks to make things more difficult for thieves.

Fits very nicely and with good distance. Nice strong lock.

UPDATE 5/30- Kryptonite asked for a pic of the damage, which I sent. They immediately shipped me a new lock and sent me a ups label to send the damaged one back. All during the Covid-Crazy! First rate service, nice to get that these days.UPDATE 5/15- Was tightening the spline screw with the supplied wrench and the screw stripped out. Later, on my first ride with it mounted, the spline loosened and the lock rotated in the mount and was rubbed by the back tire, damaging the finish on the shackle down to the metal. Submitted ticket, guess I'll see what they say.This is a beast of a lock. Heavy if that matters to you.Key and bolt operation is smooth as silk.Only con is the mount, I'm scared the lock is heavy enough to break it if I hit a curb or other sharp bump. Only time will tell. It would also be nice if the mount was designed to be moved, as it is when you cut the rubber and strap you're stuck with that size.But the lock itself is great, 5 stars!

Works well! Easy to use, large! But it being large is a downside too, I could not get it to mount on my bike nicely/without it being in the way, so now I just have to carry it in a bag behind my bike instead. Other than that though, it's a great product so far. Seems very very sturdy, difficult to cut through, even though I've heard that people have cut them...hope it doesn't happen to me!

I use it to lock my bike in the building’s garage. I’m still paranoid enough that when the door broke I took the bike upstairs but the size makes it really easy for me to lock and unlock my bike and I feel like it keeps her safe down there.

I saw some negative reviews regarding "key/lock would not work". That happened to me, so I took closer look at the lock and noticed the one rubber ring that aligns the lock cartridge was out of place. When I aligned the rubber rings correctly, all was well. So first check the rubber ring alignment if having trouble.

The lock will not stay affixed to my bike given the flawed design of the attachment piece. The lock needs to be tightened every two or three times I ride my bike. It is immensely frustrating and inconvenient. Additionally the rubber pieces at the end of the “U” keep sliding out of place and making it difficult to lock the lock. Overall I am very disappointed in this product and the vendor’s handling of the situation

Men don't like to read directions, it's true. I'm guilty. When I read the directions, trusted the process, I understood how this thing mounted. At first I thought it was broken or just poor design. It's actually genius who it straps around a pole and clamps to it. It's been on my scooter for 6 months, takes lots of bumps, and hasn't come off.The lock itself -- what's there to say. Nobody is going to steel your ride when they see it. If so, they better come with some serious grinders and make a ton of noise.