The RockyMounts Carlito U-lock is touted as the lightest U-lock on the market. Its compact design offers security while being convenient to carry, easily fitting in your pocket or bag without weighing you down. It has a security level 4 rating and features a silicone overmold for enhanced durability. The shackle size is specified as 76mm x 128mm, and the Carlito U-lock comes with three keys included.