Weighing less than 1lb, the RockyMounts Carlito is the lightest U-lock available.
A stronger theft deterrent than a cable lock while just as lightweight.
Made with a thick 14mm aluminum shackle over-molded with pure silicon for frame protection.
So light that it does not include a frame mounting bracket, just toss it in a bike bag or rear pocket or hang it from the seat rails.
Add a double ended cable to secure your wheels to the U-Lock for greater security.