Bike U-Lock - (24 cm) - Black



Made for securing your bike on long stops for as long as required.
Sturdy bike lock for securing the frame and wheel of your bike.Easy to carry thanks to its frame mount.


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Theft resistantHigh-security bike lock B'SECURe label rating: 7 out of 10.
Volume24 cm shackle. Secures up to 2 bikes to the frame or 1 bike w/ wheel + frame.
LightweightWeight 1,4 kg.
Easy transportUniversal bike-frame mount.
Warranty2 Years
Technical Information

Unlike what many people may think, tamper-proof locks do not exist. A bike lock is there to make stealing the bike more complicated, to delay the thief and therefore act as a deterrent. A good lock has an anti-picking lock mechanism and is made out of materials requiring the use of specific tools, therefore making theft more difficult.
The B'SECURE label
The B'SECURE label is the only universal anti-theft certification, which helps you buy a lock that's suited to your use. In order to do that, B'Twin has defined a test protocol with an independent laboratory, the CNPP, based on real-life theft techniques. Using this unique protocol, each model can be given an anti-theft rating from 0 to 10.
Lock body
Tube section is 13 mm thick and made from ultra-strong cemented steel.
Pick-proof lock. Hundreds of different keys to limit the risk of theft. Comes with 2 numbered keys.
Information / Concept / Technology
Structure : 70.0% Steel, Structure : 30.0% Acrylonitrile butadiene styrene (ABS)


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Decent lock.
Used for 2 to 8 weeks
Does the job of keeping my bike secure.
Key snapped inside
Just snapped the key inside my.lock, any suggestions how to open the lock?
Response of the brand
Such bad luck with the key snapping off inside the lock. I've had a mooch on the web and found a few interesting solutions on this topic.
This video seems good and after having read other posts, most seem to agree that this is the best method:
Peter Lazarus UK Cycling Market Manager DECATHLON
Lock does the job
Used for 3 to 6 months
I've used this lock for a few months and my bike has not yet been nicked. It is heavy but also strong.
Cannot mount it on bike frame
Used for 2 to 8 weeks
Because the keyhole is 180 from where shackle fits into the barrel it is impossible to mount in central space in frame as not enough room to get key in
Good price strong and good looking lock
impossible to mount inside frame
Response of the brand
Hi Chris,

Thank you for reviewing the bike lock 720. I do agree that the design/positioning of the lock isn't the best if you want to mount the lock to the bike as intended. It will fit fine with the bigger frame bikes but not so much on the smaller frames, you need to have the lock at a slight angle to make it 100% useable. If you are unhappy with the lock you have 365 days to return it with a receipt or decathlon card. 

Rob Basnett b'Twin Product Expert DECATHLON
Very sturdy lock offers good security.
This is a very sturdy lock, and the metal loop is much thicker than in the picture (which actually makes it look rather flimsy). This lock is big enough to secure the back wheel and frame of my bike to the rack at the same time. It's survived at least one attack so far - came back to my bike having left it out all day and the lock was covered in scuffs and scratches!!! Really pleased with the level of security this lock offers for the price.

The only downside is that the bracket that comes with the lock (allowing you to carry it on your bike frame) is very cheap and nasty, and the plastic grubs which are used to tighten the bracket snapped whilst I was fitting it to my bike. I then had to use a hacksaw to remove the now useless bracket.

Overall, a great lock which is definitely worth your money, but make sure you throw that bracket straight in the bin!
the lock is good, but the bracket is weak
Used for 2 to 8 weeks
grub screw on bracket/holder failed
grub screw on bracket/holder failed
Used for 2 to 8 weeks
Really easy-to-use but too heavy.
easy to use
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