Kryptonite Keeper 12 STD U-Lock with Bracket for Bicycles - Black

Cold. This is a better lock (double locking, sold secure silver) for a lower price: Kryptonite Keeper 12 STD w/bracket Lock - Black, Standard amzn.eu/d/4…Nsb

given it's sold secure bronze and often golds aren't that more expensive i'd opt for those rather than this

I have two of them and lock my bike only on very public places + take the saddle with me but there is still a good chance that some scum bag will cut through it so best advise for the UK is to be with your bike at all time

Bear in mind that this is the older keeeper with the lock that sort of goes it at an angle, rather than the more regular design of the new keeper.

Angle grinder will get through this in about 15 seconds; bear that in mind when considering if it's suitable for the bike you intend to use it with.

Superman doesn't use this, I don't know why , any ideas

Weird they still make this bent fork type. The extra machining required to make the double lock type is minimal. especially if you make millions of the things and its much sturdier. My girlfriend has one for 15 years and it survived a brutal attack in Brighton and is still useable.