The Kryptonite KryptoLok Series 2 Standard U-Lock combines the security of a U-lock with the versatility of a cable lock. With this lock, feel confident that your frame and rear wheel are fastened to the rack while the cable adds a deterrent to your saddle and front wheel, or maybe a pannier or two. It's our favorite U-lock for ease of use, with a bent-foot design that makes locking up a breeze. This lock has been around for a while, and it's nearing classic status; secure yet straightforward and iconic yet well-designed. The Series 2 won our Best Buy award for providing good quality at a more than decent price.
We compared the Kryptonite Series 2 Standard U-Lock most closely to the similar OnGuard Bulldog DT U-Lock, and the 40+ years of Kryptonite design experience kept the Series 2 scoring ahead or on par to the Bulldog in all categories. The company gives this U-Lock a 6 out of 10 on their in-house security rating, and they provide a $1,750 bicycle protection offer. We say sign up for the offer and ride around feeling like you own a secure, smart, and classic bike lock. The Cocoweb Armbar Combo is an inexpensive alternative, although the included mount isn't great and it doesn't come with an anti-theft program.