When we're commuting or traveling, we're not psyched about stuffing a bulky U-Lock in our bags, but that's why we're carrying the KryptoLok 610 S Key Folding Lock on our bike. Hardened steel links with durable rubber coating are easily utilized to prevent theft and attacks, and the best part is that this lock fits securely to our bike frame. Its click tight transportation bracket keeps our lock safely secured to our bike, even if we're riding over shifty surfaces.