Kryptonite Kryptolok Standard Bike U-Lock, Heavy Duty Anti-Theft Bicycle U Lock, 12.7mm Shackle with Mounting Bracket and Keys, High Security Lock for Bicycles Scooters,Black

I used to have this lock and a chain lock on my bike. One morning I found the chain lock gone but this one still remaining.I also used to sleep over at my girlfriend's place weekly. Every night I'd park my bike in a dark, dingy corner with no cameras. Every morning I'd wake up to more of the shackle missing rubber and more chipping in the metal. I still have yet to replace this lock.

I purchased this as a replacement for a 5 year old version which sadly was going belly up. My first purchase of this type of lock was through a different store other than Amazon and I paid approximately $20 plus tax. Inflation has obviously taken it's toll as the new one was almost 3 times the cost of the original. It appears to be the same quality though. Should it last as long or longer then it's worth the cost. Actually, it's worth the price in protection against bicycle theft. I don't live in a city like Los Angeles or New York. I live in a city of approximately 100K. Bike theft here is real. I've known people with cable locks have their bicycles stolen. My recommendation for a bicycle lock is a U-lock. Preferably a Kryptonite like this one or one of their higher quality ones meant for larger cities. It may be heavy to carry around without the provided carrier, but it's better safe and sound then seeing a high end bike be stolen with lesser locks. I personally have ridden bike exclusively for over 24 years now. My recommendations for locks are U-lock, cable lock, then chain link if nothing else.U-lock being the toughest and chain link being the weakest.

after a hoodrat tried desperately to steal my bike, he found he couldnt and began to destroy my brakes and dent the parts to my bike. I was appalled but I took it in stride. I had just walked into amazon fresh in pasadena to get some items, not realizing someone was ruining my bike outside. I came out and tried to unlock it and it was jammed! The criminal sat on a bus bench and didnt even leave!! altho, he covered his face w/ his hands! I had to go back into amazon fresh and ask for assistant. A guy in the back got BOLT CUTTERS. He just happened to have them, because he said "when employees leave they lock the storages". He broke through my severely damaged ulock offbrand that I bought here on amazon. I then realized the creep had hurt my front wheel so badly i had to drag it all the way home! I literally had to walk my bike home. I went back in and asked him to help me to make my front tire move!Thanks to the guy at the Amazon Fresh in Pasadena who was very helpful. You should tho have a bike area to lock your bike CLEARLY IN FRONT OF THE STORE and not off way to the side. This probably would have NEVER HAPPENED if you knew where to places to lock your bike.Which brings me to this lock. It took 100.00 to repair my bike and get this lock, and its nice and long, easy to turn once you figure it out and very sturdy.I will never lock my bike by far from a store. I will never lock my bike by a bus bench. I will never be out after 10 and LEAVE my bike locked where criminal element surely can exist.

The lock is just a high quality U-lock, no problems, act's as advertised. But the attachment that allows you to attach the lock to your bike is kind of wack. Instead of the high-quality metal that the rest of the lock is, it's this cheap plastic. The lock attachment is advertised to fit inside your frame, but for my size Large bike, with a water bottle holder it just didn't work out. Maybe on comfort bikes it would work, but defiantly not on a front-suspension, hybrid bike. So instead I kind of had to put it on the outside of the bike, somewhat by my gears, it was just a weird attachment process overall. I wish that there was a way instead of doing a 1/2 decent rope thing/rubber to attach, it would come with a option of just drilling, or a just a better attachment system overall. It's just annoying how nice the actual lock is, but then the attachment is so cheaply made. Again, no problems with the lock in itself, if you are just buying it to lock, and not to attach to the bike 5/5 recommend.

Someone stole it and it was locked with it

This lock is super beefy and easy to use. It’s about as lightweight of a lock as I’d use to secure our expensive E-Bikes. Make sure to register for the warranty program to further protect your bike.

I bought this bike lock after reading a recommendation from a friend, and I'm so glad I did. This lock is sturdy, easy to use, and very secure. I've been using it for a few weeks now and I have no complaints. It fits my bike perfectly and it doesn't scratch or damage it. It also comes with two keys, which is very convenient. I feel much safer leaving my bike outside with this lock on. I highly recommend this product to anyone looking for a reliable bike lock. It's worth every penny!

One of the worst locks I have ever purchased. Sure the lock is reasonably sturdy and hard to break into but that won't matter much if you can't open or close the mechanism to lock your bike. Please do not ignore the reviews that say this lock 'sticks' or has challenges with the mechanism - it is 100% true. It is not just a minor inconvenience when you have to spend 15-20 minutes playing around with the lock before it randomly decides to open. I wish I never purchased this lock.. very very frustrating. Not easy to use.