Blackburn U-Lock

This U-lock weighs 4 lbs. While it is substantial enough to provide a high level of security, you will notice the weight in your bag or mounted to your frame, so it is best suited for riders who prioritize theft protection over ultra-lightweight gear.

Yes. The lock features a weather-resistant design and rust-free steel construction, making it built to withstand exposure to the elements without compromising its locking mechanism.

Blackburn uses this rating to indicate the lock's resistance to common theft tools. A rating of 5 places this lock in a high-security category, designed to deter opportunistic thieves and withstand significant physical force.

The product description focuses on the lock's portability, but it does not explicitly include a frame-mounting bracket. You may need to carry it in a backpack or pannier while riding.

The lock is designed for durability and outdoor use, so the key mechanism is built to be reliable. However, like any mechanical lock, it is good practice to occasionally lubricate the cylinder if you live in an area with extreme freezing temperatures.