Review on 🔒 OnGuard Pitbull Medium U-Lock: Black, 3.55 x 6.90-Inch - Ultimate Security for Bikes by Demond Clenney

Very durable. I have two. A little shorter than this one. I've been using both every day for a month. There is a note on the packaging to remind the user to do maintenance 2 times a year to ensure the lock can work well for a long time. Your bike needs maintenance, so your lock probably needs it too, right? I sprayed WD-40 in the keyhole and in the lock on the side of the U-bolt, turned the key, and left the lock on the box for a day before I started using it. I'll let you know when the lock fails, but hopefully not in a few years. :)