When I used to cycle regularly, I was never quite sure what sort of bike lock to use, I settled for a D-lock for the tough protection, but it weighed an absolute ton and if I put it on the frame of the bike it would always get in the way of my knees. Being the type of person who would rather complain than do anything about it, I put up with it. If I had known these existed, I would have certainly given them ago, at only 20g they are super lightweight and at 420mm long they are so compact.