KryptoniteKeeper 12 STD U-Lock with Bracket - Black

Since the start, the key was very temperamental. It can take a good ten minutes to try to unlock my bike, it's got to a point now where I risk the bike cause it takes too long to try and lock it up. I had the lock attached to my bag for around a week because I couldn't get it off. It seems as if it's a manufacturers fault where the key doesn't actually fit the lock. Awful

I bought this based on the fact it was cheap and the star rating was good. Unfortunately didnt read the reviews, as it seems the keys not working is pretty common. After using it 5 times and being really careful locking and unlocking it it decided not to open for 5 minutes outside a shop leaving me thinking i would have to walk home. I sent it back. It really is utter crud. I'm guessing a bike thief could remove it faster than me with a key.

I bought this item 3 months ago. Initially it was awkward to fit to my new bike since the mounting options are not well thought-out. In the end I had to mount it sideways on the main vertical seat pillar, which occasionally interferes which cycling. I have found that after 3 months the lock has become unreliable and can either open first time or, on the other hand, take 10-15 minutes to undo (with either of the supplied keys), This is becoming a real pain: Although the lock seems sturdy and will probably deter thieves, I cannot recommend it to anyone (at least no-one I like) due to the difficulties I have had after only a short period of time with the lock. Some might say that the company is selling defective merchandise. however all I will say is that I will need to buy another D-lock and it will not be made by Kryptonite.

This is the worst product I have ever bought on amazon. The key was stuck in the keyhole on my second use and it was still there because of the sheet difficulty to pull it out. I rekindled the flame on my rusted and nearly fallen apart second-hand lock after this whole disaster.

Bought this as a replacment for a cheaper Wilko lock which i had snapped the key in the lock.The delivery was prompt and the lock was nicely packaged along with the holder. Although the holder was useful, i couldnt find anywhere to fit it on my bike.Nevertheless the lock works briliantly and is not too heavy. The mechanism is smooth abd it feels sturdy. I would recommend this lock and the brand in general. I have heard nothing but good things.